there hasnt been a shooting... yet... but there was a police chase in L.A., and a guy jumped out of the car with an assault rifle and went up on a roof for a bit, now he is holed up inside a house and they dont know where hes at...

he was wanted for making threats to people...

live video:

http://www.nbclosangeles.com/news/local/Officers-Pursue-Driver-LA-Freeways-262406711.html