Gunmen attacked a camp for a construction company in rural northern Nigeria, killing a guard and kidnapping seven foreign workers from Britain, Greece, Italy, Lebanon and the Philippines, authorities said Sunday, in the biggest kidnapping yet in a region under attack by Islamic extremists.

The attack Saturday night happened in Jama'are, a town in Bauchi state. There, the gunmen first attacked a local prison, burning two police trucks, Bauchi state police spokesman Hassan Muhammed told The Associated Press.

The gunmen then targeted a workers' camp for Lebanese construction company Setraco, which is building a road in the area, Muhammed said. The gunmen shot dead a guard at the camp before kidnapping the foreign workers, the spokesman said.

'The gunmen came with explosives, which they used to break some areas.'—Bauchi state police spokesman Hassan Muhammed

"The gunmen came with explosives, which they used to break some areas," Muhammed said. He did not elaborate and an AP journalist could not immediately reach the town, which is about 200 kilometres north of the state capital, Bauchi.

One British citizen, one Greek, one Italian, three Lebanese and one Filipino were kidnapped, said Adamu Aliyu, the chairman of the local government area that encompasses Jama'are. He said one of the hostages was a woman, while the rest were men. He initially had said four of the hostages were Lebanese. He blamed the confusion on incorrect information he received from his staff.

Italian news agency ANSA later said authorities confirmed an Italian had been kidnapped. It quoted Foreign Minister Giulio Terzi saying the safety of the hostage must be given "absolute priority."

Greece confirmed one of its citizens was abducted. A statement from Greece's foreign ministry said authorities had a plane on standby to send investigators to Nigeria and that its foreign minister had been in contact with Terzi.

"Two Greek police officers, liaisons in Greece's Nigerian Embassy, are in contact with their colleagues of the countries involved and the Nigerian authorities," the statement said.

Britain's Foreign Office said Sunday it was looking into the kidnappings.

No group claimed responsibility

No group immediately claimed responsibility for the abductions, though Nigeria's predominantly Muslim north has been under attack by the radical Islamic sect known as Boko Haram in the last year and a half. The country's weak central government has been unable to stop the group's bloody guerrilla campaign of shootings and bombings.

Boko Haram, whose name means "Western education is sacrilege" in the Hausa language of Nigeria's north, has demanded the release of all its captive members and called for strict Shariah law to be implemented across the entire country. The sect has killed Christians and Muslims, as well as soldiers and security forces.

The group, which speaks to journalists in telephone conference calls at times of its choosing, could not be immediately reached for comment Sunday.

Foreigners targeted in Nigeria's north

Foreigners, long abducted by militant groups and criminal gangs for ransom in Nigeria's oil-rich southern delta, have become increasingly targeted in Nigeria's north as the violence has grown. However, abductions of foreigners in the north have seen hostages regularly killed.

In May, gunmen in Kaduna state shot and killed a Lebanese and a Nigerian construction worker, while kidnapping another Lebanese employee. Later that month, kidnappers shot a German hostage dead during a rescue operation.

Gunmen who authorities say have links to Boko Haram also kidnapped an Italian and a British man last year in northern Kebbi State who were later killed during a rescue operation by Nigerian soldiers backed up by British special forces. The sect later denied taking part in that abduction, which left Italian authorities angry that the nation was not consulted before the failed rescue attempt.

In December, more than 30 attackers stormed a house in the northern Nigeria state of Kaduna, killing two and kidnapping a French engineer working on a renewable energy project.

Chinese construction workers also have been killed by gunmen around Maiduguri, the northeastern city in Nigeria where Boko Haram began.

In the most recent attack, assailants attacked North Korean doctors working for a hospital in Yobe state, stabbing two to death and beheading a third. No group claimed responsibility.

Foreign embassies in Nigeria have issued travel warnings regarding northern Nigeria for months. Worries about abductions have increased in recent weeks with the French military intervention in Mali, as its troops and Malian soldiers try to root out Islamic fighters who took over that nation's north in the months following a military coup. Last week, the U.S. Embassy in Nigeria's capital, Abuja, put out a warning following the killings of polio workers in the northern city of Kano and the killing of the North Korean doctors.

"The security situation in some parts of Nigeria remains fluid and unpredictable," the embassy said.