Police in Nicaragua say that a police officer, protester, and pro-government activist have been killed in clashes over a planned social security reform.

The National Police said the officer was killed Thursday by a shotgun blast and the protester died as a result of "a dispute between gangs." It identified the protester as a student at the National Polytechnical University in Managua.

It said the activist was killed by a gunshot in Tipitapa, a city outside of the capital of Managua where supporters of the Sandinista government have been involved in clashes.

The protests started after the government increased payroll taxes and changed pensions to try to shore up Nicaragua's troubled social security system.

The government has ordered five independent TV channels that have been covering the unrest off the air.