Federal agents conducting raids on two California cannabis farms clashed with protesters on Thursday, appearing to fire chemical munitions into the crowd.

A confrontation erupted Thursday between protesters and federal officials carrying out a raid on a Southern California farm, with authorities throwing canisters that sprayed what looked like smoke into the air to disperse the crowd.

The FBI is offering a $50,000 reward in the search for someone who appeared to fire a pistol at federal immigration agents during protests Thursday near Los Angeles, the U.S. attorney for the region said.