LAKEPORT, Calif. (AP) _ Fist fights escalated into gunfire over control of a casino that was supposed to bring in revenue and help improve conditions on a small reservation in northern California.

The struggle for control of the Pomo tribe casino on the Elem Indian Colony has left at least nine people injured during five days of violence. At least five people have been arrested.

Lake County Sheriff Rodney Mitchell has asked that the tribe's two fighting factions meet with a mediator today. U.S. Attorney Michael Yamaguchi said without elaborating that federal officials would intervene today with ``respect to the tribe's casino.''

A fist fight broke out Sunday on the reservation on the shores of Clearlake about 90 miles north of San Francisco. That was followed by an outbreak of gunfire that has continued sporadically for five days, said Rhoda Thomas, a tribal member reached at her home Thursday.

In an attempt to prevent any more gun battles, the county SWAT team was called in and surrounded the reservation, which considers itself a sovereign nation.

Many of the 100 residents have left the reservation, taking their children with them, Thomas said. Many of those remaining were holed up inside their houses, some of them armed.

Authorities counted more than 100 bullet holes in homes. They have called on four neighboring sheriff's departments for help and are patrolling the area by air.

Two men were recovering from gunshot wounds but the hospital refused to release their condition. A third man who was shot in the upper arm and chest was in good condition. The extent of the injuries of the six others who were injured was not immediately known.

The feud dates back more than a year when there was a struggle for control of the Pomo Palace and the neighboring Elem Casino, where video poker and video pool are played.

Tensions began to mount weeks ago, and on Saturday one faction of the tribe sought to oust another from its leadership in a disputed election that replaced four opponents of reservation chairman Thomas Brown.

A grand jury is investigating Brown's management of the Pomo Palace casino. Opponents accuse him of diverting profits, committing election fraud and other wrongdoing. Brown denies the allegations.