the president defending plans to slap china with $100 billion in new tariffs, tweeting, quote, china which is a great economic power is considered a developing nation within the world trade organization. they therefore get tremendous perks and advantages, especially over the u.s.

life continue to make their way north through mexico on their way to the united states. most will stop in mexico city to try to get refugee status there. most of these migrants are determined to cross the border into the united states. president trump says these so-called caravans are part of the reason why he's deploying at least 2,000 national guard troops to the border of mexico. leyla, buses still arriving. walk us through what's happening. >> i'm going to get out of the way. this is the first bus that's arrived today. this is the first person you see getting off the bus. i see right now two buses that have come in, each of them i'm told carrying about 60 to 70 people. this is the second part of the caravan to arrive here in puebla. we're already starting to see children getting off the bus, we're starting to see women getting off the bus, and this is on top of what is about 200