Updated

At least six people were stabbed Sunday when members of right-wing extremists groups holding a rally outside the California state Capitol building in Sacramento clashed with counter-protesters, authorities said.

Sacramento Fire Department spokesman Chris Harvey said emergency crews transported six people who were stabbed, some critically wounded, and that many other people had cuts, scrapes and bruises.

"There was a large number of people carrying sticks and rushing to either get into the melee or see what was going on," Harvey said.

California Highway Patrol officers managed to break up the large fight but some members of both groups remained in the area an hour after the fight first broke out, Harvey said.

The victims were all present while a protest took place, said Sacramento Police spokesman Matt McPhail.

He said it was still unclear whether and how they were involved.

The Traditionalist Workers Party had scheduled and received a permit to protest at noon Sunday in front of the Capitol. McPhail said a group showed up to demonstrate against them.

The Southern Poverty Law Center has described TWP as a group formed in 2015 as the political wing of the Traditionalist Youth Network, which aims to "indoctrinate high school and college students into white nationalism."