Two protesters were killed in the Congo on Thursday as an angry mob looted a United Nations base in the capital of Kinshasa.

• TIMELINE: Congo

Massive protests erupted following the fall of a city on Congo's eastern border.

Van destroyed during demonstration in Kinshasa. (AP photo)

Tens of thousands of people rioted across the Congo's capital, railing at UN forces they blamed for allowing rebel forces to capture the city of Bukavu.

The protesters stormed into the UN's logistical base located outside the centre of Kinshasa and began looting, a UN spokesman said.

UN forces opened fire "for reasons of legitimate self-defence," said Hamadoun Toure.

Two people died, and another was wounded in the shooting.

"We regret this deeply because our mission was to establish peace in the country. But we were left with no choice," said Toure.

A civil war in Congo officially ended in late 2002. The fall of Bukavu came after a week of fighting.

President Joseph Kabila on Wednesday accused Rwanda of helping the rebels take the strategic city.

UN officials said they had seen no evidence of Rwandan troops.

On Thursday, renegade Gen. Laurent Nkunda said his troops would leave Bukavu. He said his forces were not opposed to Kabila's transitional government, only to the government-appointed regional commander.

Nkunda said the commander had been persecuting one of the local tribes.