Updated 3:00 p.m.
Diana Sullivan, 48, of San Francisco, was killed while bicycling on King Street at Third Street Saturday at about 9:30 a.m. According to media accounts , Sullivan was run over by a cement truck driver. The crash occurred in front of the AT&T Park, where crowds of pedestrians were headed to a Giants event at the time.
Police say they’re still investigating how the crash occurred, and the driver hasn’t been cited. SFPD Sargeant Frank Harrell told KTVU , “You do have a big cement truck with a big wheel base and preliminary reports are that she was curbside on her bike, riding, and somehow became entangled.”
One commenter on SFist  who claims to have witnessed the incident said Sullivan was stopped at the red light on westbound King at Third along with the truck. When the light turned green, the truck driver pulled forward, ran her over, and caught her leg in the wheel well.
“She took a revolution and was caught between the wheel and the wheel well of the truck and then as the wheel continued to roll she landed on the street,” she said. “The trauma to her right leg, the part of her body that was caught between the wheel and the wheel well, caused her femoral artery to be severed. She bled out very, very, quickly.”
“The most awful thing I’ve ever seen,” the commenter added. “I cannot get it out of my mind.”
King has a painted bike lane in the westbound direction, but it suddenly disappears halfway between Second and Third Streets at a mid-block pedestrian crossing. At the point where Sullivan was killed, bicycle riders are thrown into mixed traffic with motor vehicles.