New cellphone footage of the night of Oscar Grant's murder has surfaced. What does it show? It seems, according to reports, a second BART officer, not Johannes Mehserle, can be seen assaulting a suspect moments before Grant's shooting death. In the footage, the officer, named Tony Pirone, goes over to one of the New Year's Day men who was sitting on the ground and clocks him square in the face. KTVU had this to say after viewing the footage:

"That was quite a shot," says Peter Keane a law professor with University of California Hastings College of Law. "That's a pretty brutal punch, knocks his head back, sends him to the ground."

After the punch, Grant can be seen putting his hands up. The two men flanking Grant sit down as the same officer appears to point a taser at them. The video then stops. Two officers arrive and that is when Mehserle shot Oscar Grant in the back, killing him. Mehserle now faces a murder charge.

No word yet on whether criminal charges will be filed against the BART police officer who threw the punch.

If you recall, Oscar Grant III was murdered on New Year's Day after getting into a physical spat on Bart. While detained at the Frutivale BART station by police, Grant, after being cuffed and pinned to the ground, was shot and killed execution style by officer Mehserle. Grant's death created quite the furor.