A breakaway Islamic extremist group has said it has killed seven foreigners who its members kidnapped from northern Nigeria, according to an online message.
The message, identified as coming from Ansaru, could not be immediately verified, though it included photographs the group claimed showed the dead, who were kidnapped from a construction company compound in February.
Those kidnapped included three Lebanese citizens and one each from Britain, Greece, Italy and the Philippines - all employees of Setraco, a Lebanese construction company with an operation in Bauchi state, local officials said at the time.
The message, posted to an Islamic extremist website, said Ansaru members killed the hostages after British warplanes were reported to have been seen in the northern Nigeria city of Bauchi by local journalists.
"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 gunmen standing over bodies.
The group said a message from Nigerian President Goodluck Jonathan that said the government would do anything in its power to free the hostages also sparked the group's decision to kill the hostages.
Ansaru previously issued a short statement in which it said its fighters kidnapped the foreigners on February 16 from a construction company's camp at Jama'are, a town about 125 miles north of Bauchi, the capital of Bauchi state.
The attack saw gunmen first assault a local prison and burn police trucks, authorities said. Then the attackers blew up a back fence at the construction company'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, leaving the Nigerian household staff members at the residence unharmed, while the foreigners were quickly abducted, a witness said.