cbs' kati weis is in the big easy. >> reporter: the big easy, the top tourist destination for american mardi gras celebrations. after the new year's eve attack on bourbon street that killed 14 people, the city is operating at tier one, the highest special event assessment rating the federal government can assign. it also means hefty security resources from hundreds of state officers and federal agents including bear cat patrols and bomb sniffing dogs. it's the first time in the nearly 200 years of new orleans' mardi gras parading for the city to see this level of support. >> the january 1st attacks changed everything for this city. >> reporter: steven stavinoha is the director at field operations for customs and border protection in new orleans. because mardi gras season started in january, his team has been here since before the super bowl. what are some of the things you're looking for? >> we're looking for that lone wolf, an individual that may be trying to do something with an automobile. we're also looking for people who may possibly have ieds in their backpacks as well as people

. >> reporter: kati weis, madison, alabama. >>> the southern california wildfires destroyed thousands of homes. most were reduced to ash. but in some cases the fireplaces and tilework still stand. turns out some of those tiles are worth saving. elise martinez reports. >> reporter: piece by piece masonry contractor cliff douglas is preserving a small part of altadena history. >> i got it. >> reporter: douglas is with save the tiles, an organization working to rescue these antique tiles, some more than a century old. >> these are called batch elder tile, started in 1910 in pasadena. they're a local tile. so that's why they're in a lot of the homes up here. >> reporter: in altadena chimneys and fireplaces are some of the only things that survived the intense heat. >> the important part is just to try to give the owners a little something back. >> reporter: douglas and his crew are working against the clock as the army corps of engineers gets ready to clear out properties. he says there are dozens of homes with these renowned tiles inside. >> and we're trying to beat the bulldozers across