BEIRUT: Calm has been restored to Zahle prison after inmates staged a protest there Friday, the Internal Security Forces said.

"After the protests staged by some prisoners in Zahle prison this afternoon, the ISF returned calm," a tweet from the agency read.

Local TV channel Al Jadeed broadcast a video showing dozens of inmates gathered in the galleries and floor of one of the prison’s wings, shouting and punching the air.

A video shared with The Daily Star showed inmates burning mattresses in the middle of an open hall.

Al Jadeed later reported that the Lebanese Army had arrived at the prison in an attempt to contain the situation.

Mass protests broke out across Lebanon Thursday after the government announced a new tax on internet-based phone calls. The tax was abruptly abandoned late Thursday night, but the about face was not enough to satisfy protesters fed up with Lebanon's political leadership.