Nigerian authorities are investigating an explosion that killed three people late Wednesday at a military facility in the oil-rich southern city of Port Harcourt.
The attack suggests that the militants responsible for recent kidnappings in the Delta are now targeting the military.
The Movement for the Emancipation of the Niger Delta has consistently alleged security forces are guilty of atrocities against the civilian population in the delta.
The group carried out recent strikes against the oil industry, which have crippled oil production by at least 20 percent.
The group has vowed to carry out more attacks against the oil industry in the coming weeks.
Delta youth leader and president of the Niger Delta Youth Council, Mike Ekamon, says the government must talk directly to the militants.
"We own the land, we know our problems," he said. "You do not pick governors and ministers to come and instill power in the people. You pick those people. Call the youth's proper. Call the egbesus [militants], those people you call militants, if you pacify them, the problem will be put off immediately. But if you do not pacify them, they will continue fighting in the creeks."
The latest attack represents an escalation of the violence at a time the authorities have launched an ambitious initiative to develop the infrastructure and social amenities in the Niger Delta, where about 20 million people live in abject poverty.
Concerns about Nigeria's political future are also adding to the rising tension in the West African nation.