Nigerian military forces stormed the hideout of a militant gang operating on the waters of oil-producing Cross River State and rescued 27 abducted oil workers, a navy spokesman said Sunday.

"It was a joint military operation involving the navy and the army. Twenty-seven oil workers were rescued on Friday, while one is still missing," Lt. Commander Ajibola Olabisi told Agence France Presse.

Four foreign oil workers who were kidnapped when unknown gunmen attacked their vessel in the Gulf of Guinea off Nigeria on August 4 have been released, their employer Sea Trucks Group said Thursday.

"They were released last night," company spokeswoman Corrie van Kessel told Agence France Presse, regarding the Indonesian, Iranian, Malaysian and Thai nationals.

Gunmen in Nigeria's troubled northeast blew up part of a primary school then attacked a Catholic church and police station before officers fought them off, police said Monday.

Separately, two gunmen riding on motorcycles opened fire on troops at a military checkpoint in the northern city of Kano on Sunday, injuring a soldier, military spokesman Iweha Ikedichi said.

Flooding caused by heavy rains in central Nigeria has killed at least 28 people, with many others still missing, while also destroying homes, bridges and farmland, officials said Tuesday.

"I have counted 28 bodies and many people are still missing after the flood," said Kemi Nshe, local government chairman for the Shendam district in central Nigeria's Plateau state.

Nigerian troops recovered weapons in raids on suspected Boko Haram bases in two northern cities, officials said Saturday.

A raid in Tudun Bayero, some 10 kilometers from Kano, northern Nigeria's largest city, was carried out early Saturday after a tip-off, Kano State director of State Security Service (SSS) Basil Etang told Agence France Presse.

Residents in central Nigeria said Thursday that police have raided scores of homes and beaten unarmed civilians while searching for the perpetrators of a church massacre that killed 19 people this week.

The police spokesman in Kogi state, where the church slaughter occurred late Monday in the city of Okene, denied the allegations.

Authorities in Nigeria's Kogi state have slapped a dusk-to-dawn curfew on a key city after a church massacre and a gunfight between militants and troops left at least 23 people dead, officials said Wednesday.

The spate of violence in Okene in central Nigeria began on Monday night, when gunmen stormed an evangelical church, cut the electricity and opened fire once the building was plunged into darkness, killing 19 people.

Gunmen have opened fire on an evangelical church during a service in central Nigeria, killing at least 19 people in the latest such attack in the country, the military said Tuesday.

"The attack was at 8:20 pm yesterday night. The attack was from unknown gunmen at the Deeper Life Church," said Lt. Col. Gabriel Olorunyomi, head of the military's Joint Task Force (JTF) in Kogi state,

A suicide bomber in a car rammed into a military patrol on Sunday in the northeastern Nigerian city of Damaturu, killing himself and at least five soldiers, a security source said.

"The attacker died in the explosion and five soldiers were also killed," the source said on condition of anonymity.

Explosions rocked parts of the northeastern Nigerian city of Maiduguri Saturday as troops engaged suspected Islamic radicals and raided homes, residents said.

The explosions, which began late Friday, occurred in three neighborhoods notorious for attacks blamed on the Boko Haram sect, and residents fled as troops went door-to-door arresting people suspected of complicity, they said.