Local officials say two police officers have been killed during a street protest in the restive western Venezuelan town of San Cristobal.

Authorities say the two were killed Tuesday amid a protest over a hike in public transportation fares in Tachira state.

The Tachira Police announced on its Twitter account that officers Nicolle Perez, 21, and Otto Marquez, 25, were killed by a bus hijacked and later abandoned by the protesters. Four other police officers were seriously injured.

Tachira Secretary of Public Security Ramon Cabeza told reporters that at least 31 people had been arrested during the protest.

Protests in San Cristobal against the country's socialist administration two years ago helped spark a nationwide street protest movement. The town's mayor was imprisoned for his involvement.