JOHANNESBURG, January 14, 2014 (AFP) - The South African government appealed for calm Tuesday after police allegedly shot two people dead during violent demonstrations over a lack of water in townships near Pretoria.

Police Minister Nathi Mthethwa "called for calm and respect for the rule of law" as residents vowed to push ahead with demonstrations, now in their third day.

Police said two people were killed on Monday during protests in Mothotlung and Damonsville, where residents have reportedly been without water for at least a week.

The force refused to comment on how they died, while the country's police watchdog has launched a probe into the deaths.

Amid outrage and allegations of police brutality, Mthethwa called on any witnesses to come forward and moved to assure angry community members that no one was above the law.

"We can assure the public that if any official is found guilty, they will face the consequences," he said.

Violent protests over substandard delivery of utilities such as electricity and water are common in South Africa, where residents vent their anger at local government by taking to the streets.

Experts say there are hundreds of similar protests each year in Africa's wealthiest country, which is dogged by stubborn levels of inequality.

But the latest protests come just months before a general election that will test the popularity of President Jacob Zuma's ANC government.

South Africa's police force has come under intense scrutiny since police shot dead 34 striking platinum miners in August 2012.

An inquiry is still underway into the Marikana massacre, no one has yet been brought to book.