felix hernandez ktvu channel 2 news. >>> back after a chaotic evening commute in downtown san francisco. demonstrators confronted police in riot gear. they also came out to protest bart's decision to cut off cell phone service during a similar situation last week but bart did not block cell phone service. >> as long as we get the compliance, we will play as well as we can that includes leaving cell phone service on. >> now there were no problems but they captured one angry bart rider who shoved somebody trying to keep the cart doors from closing. the federal agency will look into whether bart has the right to selectively turn off cell phone service and many others are also concerned. >> that is a concern and when you have these things happening, the first person they will come to is train operators and if we don't have the right information we look foolish. >> it was clearly an issue of public safety. >>> you can find more by going to our channel 2 website. just click on the home page csnne.com. >>> they responded to a carjacking -- k it uv.com. >>> they responded to a carjacking and wh