BUFFALO, N.Y. (AP) -Police investigators are growing impatient with Buffalo Bills running back Marshawn Lynch and his failure to meet with them more than three days after his vehicle was involved in a hit-and-run accident.

Buffalo Police Department spokesman Mike DeGeorge suggested Tuesday that Lynch could face an obstruction of justice charge if he doesn't cooperate. He said Lynch's lawyer finally contacted investigators on Monday, but a meeting has not been set.

``Right now, the ball is in their court. The clock would be ticking,'' DeGeorge said during a news conference. ``Police have made it clear to Mr. Lynch's representative that they would like some answers, expect some answers and if they don't start getting some answers then they could take some other action.''

Lynch took part in the Bills' voluntary practice Tuesday morning after arriving about 10 minutes late. Afterward, he avoided reporters.

The Bills distributed a statement from Lynch's lawyer, Michael Caffery, in which he declined comment and added he instructed his client also not to say anything.

Declining to call Lynch a suspect, DeGeorge said evidence and witness statements point to the player's 2008 Porsche SUV as the vehicle that sped off after striking a pedestrian early Saturday at an intersection near Buffalo's bar district. The victim, identified as a 27-year-old woman from suburban Toronto, had a bruised hip and a cut that required seven stitches, DeGeorge said.

DeGeorge declined to say whether police have determined Lynch was behind the wheel or even in the vehicle during the accident.

The SUV was impounded after being discovered near Lynch's home shortly after the accident. DeGeorge said police were unable to contact Lynch over the weekend, and even attempted to reach him through the Bills.

DeGeorge said police were not allowed to approach Lynch at practice because he has invoked his right to representation by an attorney.