US forces have carried out an air strike targeting the British Islamic State militant known as "Jihadi John", the Pentagon has said.

Mohammed Emwazi, the Kuwaiti-born British militant, was the target of an attack near Raqqa, in Syria.

A worldwide hunt had been launched for Emwazi after he was seen in videos of the beheadings of Western hostages.T

The Pentagon said it was still assessing whether Emwazi had been killed in the attack on Thursday.

A US official told the BBC the strike had been on a vehicle believed to be carrying Emwazi, whom the official said had been "tracked carefully over a period of time."

The Associated Press news agency reported a US official saying that a drone had been used in the attack.

Pentagon press secretary Peter Cook said: "We are assessing the results of tonight's operation and will provide additional information as and where appropriate."

A Downing Street spokeswoman said: "We are aware of the US statement about the air strike targeting Mohammed Emwazi. Like them, we are not commenting further at this stage."

Emwazi is believed to have travelled to Syria in 2013 and later joined so-called Islamic State militants.

He first appeared in a video in August last year, when footage was posted online showing the murder of US journalist James Foley.

He was later pictured in the videos of the beheadings of US journalist Steven Sotloff, British aid worker David Haines and UK taxi driver Alan Henning, as well as American aid worker Abdul-Rahman Kassig, also known as Peter, and Japanese journalist Kenji Goto.

In each of the videos, the militant appeared dressed in a black robe with a black balaclava covering his face.

Initially dubbed "Jihadi John", he was subsequently named as Emwazi, from west London, in February.

(BBC)