A 45-year-old man is in a Valley hospital in "extremely critical" condition after he was run over by a cab yesterday afternoon.

After running the man over, the cab driver just took off -- and there might be a reason: he was seen arguing with the man who was run over just moments before hitting him with his cab.

Police say witnesses watched the cabbie and the victim arguing at a convenience store at 15th Avenue and Indian School Road right before the man was hit by the cab.

Witnesses spoke to KPHO and give the following account:

"They hit him because they got in an argument because of some kids. The kids were in there getting hot dogs or something," said witness Aaron Kelly.

Then the two took the argument outside. A witness says that's when the verbal disagreement turned physical.

Richard West Jr. says, "They were yelling. The taxi was like that and the victim was like yelling 'I want a ride right now,' and I guess the taxi said, 'No because I am going to pick up somebody,' and then that's when it hit him. It just hit him like that."

Police detained the driver shortly after the incident. The identities of the driver and the victim have not yet been released. Phoenix police have not yet said whether the cabbie will be charged with a crime.

Check back for updates.