Thirteen people were arrested following the melee, including one Klan member who is accused of stabbing a counter-protester with a flagpole, said Anaheim Police Sergeant Daron Wyatt.

Several counter-protesters were taken into custody after stomping a KKK member on the ground, Wyatt said.

Wyatt said the altercation took place as soon as several Klan members arrived at the park about a mile north of Disneyland, for a planned rally there.

"As soon as they got out of their vehicle, immediately they were attacked by counter-protesters and this caused a melee down the block," he said.

Wyatt said four people were wounded in the ensuing confrontation. The person most seriously wounded was stabbed with a flagpole that had an American eagle finial at the top and taken to a local hospital in critical condition.

Several witnesses said that a peaceful counter-protest had been under way for about three hours when the Klansmen arrived in a black SUV.

The vehicle pulled up and three men got out and began to unload signs when the group of about 50 counter-protesters approached them, yelling and throwing sticks, witnesses said.

"Three people were stabbed by the fire hydrant," said Darren Simpson, 49. "These Klan guys were fighting for their lives."