Nigerian troops patrol oil city

Armed gangs of militant youths roam the swamps and creeks

Troops have been deployed to the oil-rich southern city of Port Harcourt in Nigeria following two days of clashes.

At least five people were killed in fighting when two suspected cultist groups exchanged heavy gunfire on Sunday night and Monday morning.

The police, navy and army will jointly patrol the waterfront area, a police spokeswoman said.

Gangs vying for territory in the area are involved in the lucrative business of siphoning oil from pipelines.

They then use the proceeds to buy weapons which fuel inter-ethnic conflict between the Itsekiri and Ijaw.

Turf war

"The troops are on intensive surveillance of the area to flush out the militias," Rivers State police spokeswoman Barasua Ireju told AFP news agency.

Fighting for Nigeria's oil

Journalist Naphtali Tope Brown told the BBC's Network Africa programme that several houses had been destroyed in the violence, and in unrest last week another 10 people had been killed in Port Harcourt's Njemanze suburb.

The governor of River State issued an edict promising to prosecute anyone involved in gangsterism or cults, even if they were government officials, Mr Brown said.

According to Rivers State government spokesman Emmanuel Okah the gangs are well armed and are involved in a turf war.

"The battle is purely economic. The cult groups are fighting for supremacy and control of the oil producing areas so that they can carry out their bunkering activities," he said.

Nigeria is Africa's biggest oil exporter, but the Niger Delta region - the centre of the country's oil industry - is one of the most underdeveloped areas of the country and is prone to violence.

Sometimes armed militant youths kidnap oil workers and hold them to ransom for money

But most of the time armed gangs roam the swamps and creeks stealing crude oil from pipelines.