under the cover of darkness, thousands of troops from all across the uk and around the world are preparing. their mission dash to ensure the king's coronation passes without a hitch. just days before millions tune in to watch the coronation... they are able to practise their movements along the procession route.

bagpipes skirl it is the biggest military ceremonial event seen in this country for seven decades. since the coronation of queen elizabeth ii in 19 for three. "1953. elizabeth ii in 19 for three. —— 1953. tens of thousands of people will line the procession roots and tens of millions will watch around the globe. so the pressure to make sure no foot or horse is out of place is huge. just some breaking news to bring you, this related to buckingham palace, police say they have arrested a man outside the palace. it they have arrested a man outside the palace.- they have arrested a man outside the palace. it is early tuesday night. _

outside the palace. it is early tuesday night. hours - outside the palace. it is early tuesday night. hours before | outside the palace. it is early i tuesday night. hours before the rehearsal is due kick off. right in front of buckingham palace. a reminder of the important role the security services will play, making sure everything goes according to plan. they man is detained by police after suspected shotgun cartridges were thrown into the palace grounds. cordons were put up in the area and a precautionary controlled explosion carried out. it is being treated according to the met police as an isolated mental health incident. once the security incident concludes... the military rehearsal gets under way.

to the delight of those who made their way specially to watch, and the surprise of people who just happened to find themselves surrounded by thousands of service personnel. for those who are very brave members of the public to stay up members of the public to stay up all night, we used to call these things in early—morning rehearsal and now it is very much an overnight rehearsal. from eight o'clock last night you had thousands of troops from the army coming to this assembly area in wellington barracks and everyone was forming up and heading out to

their various points, either street lighting on the procession ready to step off. it is very rare that you get all regiments of the household division together with all the colours, that is a really special occasion, and just a unique moment in our history. there are two processions. one takes the royals from buckingham palace to westminster abbey. buckingham palace to westminsterabbey. it buckingham palace to westminster abbey. it is known as the kings procession.

we are the very front horse of the entire king's procession from buckingham palace to westminster abbey and then back again safely. it is absolutely incredible. it is not only a once in a career opportunity, but a once—in—a—lifetime opportunity and i am so lucky to be given the chance to do that. the return journey back through the streets of central london is known as the coronation procession.

both will be scrutinised in exacting detail. tonight, it must be rehearsed, finessed and made ready for the big day. as well as the military, the carriages set to be used are all part of the rehearsal. on the way to the abbey, the royal party will travel in the diamond jubilee state college. —— state coach. used for the first time at the state opening of parliament in 2014, it has electric windows, air—conditioning and shock absorbers, making for a comfortable ride.

it is an important day for everyone involved. lots of care and preparation has been taken to ensure every movement and formation in the king's coronation is perfect. up up until now, rehearsals have had to take place outside of the capital. tonight, troops can practice moving around actual monuments. every step carefully observed under the watchful eye of

senior officials on the lookout for any potential problems. under the cold night sky, the band marches on. the procession then reaches westminster abbey.

the moment of arrival. rehearsed exactly as it will be on coronation morning. the steps of the diamond jubilee state coach iris carefully unfolded to allow the king and queen consort to safely dismount. —— are carefully unfolded. the root travels along some of the busiest roads in central london. —— route. they cannot

simply be closed off every time there is a need to practise the drills. you are on the streets you are going to be parading on on saturday, and therefore, for each person operate they are looking for the small details, the small markers, the ground they have too much across, the distance they are from people in front and behind and they will be focusing rather more on that then the crowd behind the crowd barriers. the that then the crowd behind the crowd barriers.— crowd barriers. the entire route is — crowd barriers. the entire route is mapped - crowd barriers. the entire route is mapped out - crowd barriers. the entire i route is mapped out another using a pace stick, keeping everything at the correct distance.

while the ceremony is happening inside the abbey, personnel will form up on whitehall and the mall. bend around, then around. they will set off— bend around, then around. they will set off as _ bend around, then around. they will set off as soon _ bend around, then around. they will set off as soon as _ bend around, then around. they will set off as soon as the - will set off as soon as the king and queen leave westminster abbey and join the rear of the procession. the ceremony inside the abbey is set to last two hours, after which the newly crowned king and queen will return back to buckingham palace. the timekeepers with stopwatches at the ready expect it to be not long after 1:30.

next time these soldiers walked down the streets, they, officials hope, will be aligned with crowd. all aiming to get a look at the royal couple. well into the early hours, they march on.

tonight, the streets are empty. come morning, they will be full once more. number one division, prepare to host... number one division... march!

on the day, there will be a long wait while the service continues, possibly in the rain and in full view of the crowds who will be lining the street. eyes forward and wait for the command.

i think the important thing is everyone involved puts a huge amount of work into it and the professionalism and skill of the young men and women of the armed forces will deliver an amazing parade on saturday. king charles and queen camilla will travel back to buckingham palace in the gold state coach, just as queen elizabeth ii did in 1953.

bells pealing. it is the most spectacular looking coach, notoriously uncomfortable though, with the late queen describing writing on it as horrible. at 260 years old, it does not have modern commodities and no shock absorbers to smooth the ride.

the return journey is a much grander affair involving 12,000 military. band plays bagpipes skirl. as well as

looking spectacular, the procession will sound extraordinary as well. marching bands from all three armed forces will provide this staring music guaranteed to get the crowds tapping. —— staring music. —— stirring music. marching band plays.

iam

i am immensely proud because i've been involved in the planning since november. it means an awful lot and seeing the scale of the event over last night and seeing 7000, 8000 personnel in london delivering that event was incredible but i am also looking forward to see how the nation reacts on saturday because it is going to galvanise the nation and hopefully will appreciate what unites us and not what keeps us apart. marching band plays. orders given. the late queen's procession back to buckingham palace took around two hours and was much,

much longer than king charles will be for such a travel around much of central london including regent street and piccadilly service. —— piccadilly service. —— piccadilly circus. on saturday as at rehearsals practised tonight, the king and queen the return of the way they came with the journey back expected to take around 33 minutes. marching band plays.

asa as a commander—in—chief with the armed forces, the monarch has a special link with the military and so after the profession is finished, they will be joined profession is finished, they will bejoined by king charles and queen camilla who will receive a royal salute. marching band plays. a successful rehearsal. now, onto the main event. as the sun rises over london, the armed forces returned to their accommodations. they know, come saturday, the drills practice tonight will be recorded in history forever. —— practised.

marching band plays. hello there. the coronation is almost here and the heavy showers that we had on friday, those have been fading away. we had some late in the day lovely rainbows but earlier on, there was a lot of thunder and lightning. those have pushed clear but we need to look to the south now, into the english channel. this is where our weather is now coming from, the cloud thickening up and these weather fronts will bring some rain. so, this is the forecast for the coronation in central london. looks cloudy, there'll be some rain from time to time. temperatures are not going to be as high as the 20 degrees that we had on friday. we start with ten degrees in london first thing on saturday, seven or eight further north, just one of two

showers left over here but we've got this patchy rain here developing in southern england, moving steadily northwards into wales, the midlands, eventually into east anglia and lincolnshire. for northern england, scotland, northern ireland some sunny spells breaking out but also some heavy showers developing. in between those heavy showers in the sunshine, temperatures could reach 17 or 18 degrees. under the cloud and the rain across england and wales nearer 14 or 15 celsius. there could be some wet weather into the night as well before finally pushing away out into the north sea and then, we'll see some sunny spells on sunday but also some showers. more likely to have those showers in scotland and down the eastern side of england, so further west, you may get away with a dry day. with some sunshine around, it should be a bit warmer for most areas — temperatures peaking at 20 or 21 across the south—east in the afternoon. but if we look to the west, more weather fronts are beginning to pile in from the atlantic and during the evening and overnight, we're going to find rain pushing its way eastwards across the whole of the country, so bank holiday monday starts cloudy with some rain around as well. that rain may be pushing its way eastwards but it will be followed by some

sunshine and some showers. these could be heavy and thundery, particularly in northern ireland and western parts of scotland. temperatures, while not quite as high, at around about 16—18 degrees. so, a real mixture of weather, i think, over the coronation weekend. unfortunately, there is rain in the forecast for many of us. wet weather developing on saturday. fewer showers on sunday but then, we're back into some heavy showers on monday. and this very mixed picture continues into next week. we're on the cooler side of the jet, so temperatures nothing to write home about. there'll be some sunshine but showers never too far away.

live from london, this is bbc news. countdown to the coronation: this is the scene live in central london where thousands are gathering to witness an historic moment. king charles iii will be crowned here at westminster abbey in the uk's first coronation in 70 years. i'm louisa pilbeam live on the mall. i'll be talking to some of those who've been camping out overnight for a prime spot on the procession route. scotland yard says the coronation will involve the biggest ever single deployment of police officers in london, protecting those in the crowd, as well as hundreds of vips.