Animal rights activists in Brazil have clashed with police after freeing dogs from a laboratory where they were used to test drugs.
The clash came one day after activists broke into the Instituto Royal laboratory in Sao Roque and released 178 beagles.
About 500 activists tried to break through barriers set up in front of the laboratory following Friday's break-in.
Several members of the so-called Black Block anarchist group were among the protesters, said Officer Edivaldo Nunes of the Sao Roque police department.
"They hurled rocks and set fire to a police car and to two cars of a local television station," Nunes said, adding that police responded with tear gas and pepper spray to disperse the crowd. He did not know if anyone was hurt or arrested.
He said "a large group of activists shouting 'save the dogs' stormed the lab early on Friday and drove away with the animals.
He said none of the dogs have been recovered.