Police in Congo Republic have shot dead three protesters during a demonstration against a constitutional referendum that could open the door for the long-time president to a new term in office.

Police forces used live ammunition to disperse the protesters in the capital, Brazzaville, on Tuesday.

Reporters and witnesses confirmed that they had seen at least three bodies at the central morgue in Brazzaville.

An unnamed witness who brought one of the bodies to the morgue told Reuters that his friend had been gunned down by police. “I was there when they opened fire. I was lucky it wasn't me who was killed.”

At least six people were earlier injured in weekend clashes in the second largest city of Point-Noire.

On October 17, Prosecutor Andre Galaka Oko warned of “very heavy penalties” for those who threaten public order in the country.

Families across major cities have been stocking up on food over fears of violence in the coming days.

The opposition has called for a protest over President Denis Sassou Nguesso’s bid to extend his three-decade stay in power.

On Sunday, mobile communications were cut in the capital just ahead of a rally against the referendum.

Politicians campaigning against the October 25 referendum have called for a campaign of “civil disobedience.”

The 71-year-old president is barred from seeking re-election when his second term expires next year. The referendum calls for the limit of two terms to be scrapped as well as changing a regulation preventing candidates older than 70 years to run for president.

Nguesso was elected into office in 1997 and had previously ruled Congo from 1979 to 1992.