Riverside County Sheriff Stanley Sniff on Tuesday called on federal authorities to shut down the Soboba Casino, saying that the tribal council had ordered security officers to block or delay his deputies from entering the troubled reservation, where five members have been shot to death during confrontations with his department.

Sniff told the Riverside County Board of Supervisors on Tuesday that he sent a letter to the National Indian Gaming Commission on Monday, asking authorities to suspend the casino's operating license.

He added that tribal leaders and security officers could face arrest if they interfere with law enforcement on the reservation.

"The tribal council has directed tribal officers to block officers coming onto the reservation," Sniff told the supervisors. "This is a violation of the law. Allowing an isolated pocket of lawlessness to exist is simply not an option. The residents deserve better than this."

The announcement comes two weeks after Sniff and Soboba Tribal Chairman Robert Salgado signed an agreement designed to ease tensions on the San Jacinto-area reservation.

Salgado denied blocking any deputies.

He said officers, like everyone else, are required to stop at the gates of the reservation and tell security why they want to be admitted.

"We haven't changed any policy. We check everyone who comes in and goes out. If they got a warrant they can come on but they have to stop first," he said. "They can't just come on and cruise or patrol. That's not legal."

david.kelly@latimes.com