West African leaders attended a meeting in Paris and agreed to wage war on Boko Haram after militants suspected to be from the rebel group attacked a Chinese work site in northern Cameroon on Friday.

At least 10 people are believed to have been kidnapped, the regional governor confirmed yesterday. The Chinese embassy in Yaounde confirmed the attack at a site near the town of Waza, 12 miles from the Nigerian border close to the Sambisa forest, a Boko Haram stronghold.

The Islamist group kidnapped more than 200 girls from a school on the Nigerian side of the border last month and Nigerian troops backed by foreign units are searching the area around the forest for them. Outrage over the kidnapping of the schoolgirls has prompted Nigerian president Goodluck Jonathan, criticised at home for his government's slow response, to accept US, British and French intelligence help in the hunt for the girls. Boko Haram has killed more than 3000 people in a five-year campaign to establish an Islamic state in mostly Muslim northeast Nigeria.

Yesterday, before the Paris meeting, British Foreign Minister William Hague confirmed that the UK has offered to send advisers to help Nigeria's military structure its efforts to fight the militants.

"Nigerian security forces have not been well structured for this kind of thing and that has been shown by the problem getting worse," Hague told reporters.

"We can help with that which is why we are offering to embed military advisers within the Nigerian headquarters."

Echoing Hague's remarks, French president Francois Hollande said that Boko Haram was now a threat to west and central Africa and it was linked to other militants, including al-Qaeda's north African arm.

"Boko Haram is a major threat for all of western Africa and now central Africa with proven links to AQIM (al-Qaeda in the Islamic Maghreb) and other terrorist organisations," Hollande told delegates at the Paris summit.

A comprehensive plan to exchange information, co-ordinate action and protect borders needed to be put in place immediately, Hollande added.

With about 6000 troops operating in either Mali to the northwest or the Central African Republic to the east, Paris has a major interest in preventing Nigeria's security deteriorating.

Friday's attack on the Chinese work site in Cameroon began when power was cut in the evening. A five-hour gunfight followed, a guard at the Waza National Park told reporters.

"Some of us decided to hide in the forest with the animals," the guard said.

Nigeria has complained the far north of Cameroon is being used by Boko Haram militants to shelter from a Nigerian military offensive and to transport weapons, and has urged Cameroon to tighten border security.

Cameroon said in March it would send 700 soldiers to its northeastern border as part of efforts to tackle the armed group

"The first focus is about the girls, but that requires these countries work together, particularly Cameroon and Nigeria who have not enjoyed strong, positive relations in recent years," Hague said.