Nigerian militants in the restive Niger Delta appear to be making good their promise to cripple the country's petroleum industry, targeting oil company employees and attacking facilities in the oil-rich region.  Gilbert da Costa in Abuja reports the Nigerian authorities are playing down the likelihood of a major military response to recent attacks.

Nigerian militants are on the offensive again; blowing up oil pipelines and seizing oil workers.  Violent attacks and kidnappings targeting oil companies are now a frequent occurrence in the Niger Delta. 

Some are carried out by rebels claiming to be fighting for a greater share of the region's oil wealth for local people, others by criminal gangs out to make ransom money.  More than 200 foreigners have been seized in the Niger Delta since early 2006.  Almost all have been released unharmed.

Security forces protecting the oil industry have also come under frequent attacks, an indication, some say, that government security forces are losing control in the area.  Military crackdowns have had little effect on the rebellion.  But the Nigerian chief of defense staff, General Owoye Azazi, says the mandate of the military in the Niger Delta is to contain the insurgency.

"The military has a role of stabilizing the environment in the Niger Delta for political solutions, for economic solutions.  The military is not conducting an all-out warfare.  So there are constraints.  You are talking about operating in communities where you have about 98- to 99-percent law-abiding citizens and a few other elements," he said.  "So how do you operate fairly to justify whatever action you are going to take?  So those are the conditions under which the military operate in the Niger Delta."

Oil production has slowed due to sabotage and President Umaru YarAdua is under pressure to halt what has become a major problem for the government.  The government's attempts to negotiate a settlement with rebels have collapsed.

The picture is complicated by a web of vested interest, from local warlords, corrupt local politicians and federal officials benefiting from a multi-million-dollar trade in stolen crude, and members of the security forces accused of gun-running.

The conflict has simmered for more than a decade and analysts fear using a military option could further complicate the crisis.

Local media reports say the Nigerian military killed 12 rebels and arrested about 60 last week in a crackdown to end criminal activities in the region.  A military task force protecting oil workers and facilities carried out the raids.