Sustained gunfire erupted Tuesday in Lubumbashi, DR Congo's second-largest city, where large numbers of police have been deployed on the last day of President Joseph Kabila's mandate, an AFP correspondent said.

The firing started at 9:15am (0715 GMT) in the Matuba neighbourhood in the south of the city where demonstrators and police have clashed, with streets strewn with rocks and burned tyres, the correspondent said.

The gunfire was intense for about 20 minutes, and then became more intermittent, he said.

Earlier in Matuba, a policeman told AFP that his men were facing hostile groups of demonstrators.

Three of the demonstrators were armed, added Jean-Claude Kazembe, governor of the Upper Katanga district which includes Lubumbashi.

"This is what justifies police shooting live rounds in the air to disperse civilians," he said.

Lubumbashi is a stronghold of Moise Katumbi, an opposition leader who had been hoping to run in the presidential election which has, however, been postponed indefinitely.

Kabila has been in power since 2001 and the constitution bans him from running again.

But since he appears set to be hanging on to power, tensions in DR Congo have been running high, with police massing in the cities and many people staying home to avoid violence.