What was blocking traffic on 290 inbound this morning? 1/13/24

My wife was heading into town this morning and her navigation said 290 was clear but as she approached Beltway 8 it pretty much became a slow crawl all the way to 610. Then it was clear. She could see red flashing lights up ahead of her but could not see what was the issue. Guessing some sort of rolling blockade for some reason. Was anyone else in this mess? Any ideas what it was?