Ansaru says it has killed seven construction workers, including a Briton, kidnapped last month in raid on company camp

This article is more than 7 years old

This article is more than 7 years old

A Nigerian Islamist group claimed it has killed seven kidnapped foreign construction workers, including one Briton.

Ansaru kidnapped seven employees of the Lebanese construction company Setraco a week ago. Three of the workers were Lebanese, while the other four were from Britain, Greece, Italy and the Philippines.

A message was posted on an Islamist website on Saturday that claimed Ansaru members killed the hostages after journalists saw British warplanes in Bauchi, northern Nigeria.

"As a result of this operation, the seven hostages were killed," the group said in the statement. It said a video of the killings would be posted online. An online image accompanying the posting appeared to show a gunman standing over dead bodies.

The Foreign Office said it was urgently investigating the claims.

Ansaru previously issued a short statement in which it said its fighters kidnapped the foreigners on 16 February from a construction company's camp at Jama'are, a town about 125 miles north of Bauchi, the capital of Bauchi state.

During the operation gunmen attacked a local prison and burned police trucks, authorities said. They then blew up a back fence at the construction firm's compound and took over, killing a guard in the process, witnesses and police said.

The gunmen appeared to be organised and knew who they wanted to target, abducting the foreigners quickly while leaving the Nigerian household staff members unharmed, a witness said.

In January 2013, Ansaru declared itself a splinter group independent from Boko Haram, the north's main terrorist group, analysts have said. Boko Haram, which means "western education is sacrilege", has launched a guerrilla campaign of bombings and shootings across Nigeria's predominantly Muslim north. It has been blamed for at least 792 killings last year alone, according to an Associated Press count.

Britain previously linked Ansaru to the May 2011 kidnapping of Christopher McManus, who was abducted with Italian Franco Lamolinara from a home in Kebbi state. The men were held for months before their captors killed them in March 2012 during a failed Nigerian military raid backed up by British special forces in Sokoto, the main city in north-west Nigeria.