Gunmen killed two more people during political unrest in Venezuela on Monday, bringing the total number of deaths to 12 this month, as anti-government protests entered a fourth week with mass "sit-ins" to press for early elections.

A 42-year-old man who worked for local government in the Andean state of Merida died from a gunshot in the neck at a rally in favour of president Nicolas Maduro's government, the state ombudsman and prosecutor's office said.

Another 54-year-old man was shot dead in the chest during a protest in the western agricultural state of Barinas, the state prosecutor's office added without specifying the circumstances.

Seven others were injured.