Image copyright Unknown Image caption Junaid Hussain referred to himself as Abu Hussain Al Britani

A British man described as a "top cyber jihadist" has been killed in a military drone strike in Syria, US officials say.

They said Junaid Hussain, 21, a convicted computer hacker from Birmingham who fled to Syria in 2013, had been a "high-value target" within the Islamic State group.

The US called it a serious blow to IS.

Michael McCaul, chairman of the Homeland Security Committee, said his death sent an "unmistakable message".

"We need to maintain vigilance and good intelligence to stop future plotting, and ultimately we must destroy the group's terrorist sanctuary," Mr McCaul said.

Earlier, a UK government spokesman said: "We are aware of reports that an Isil terrorist of British nationality is believed to have been killed in a coalition air strike in Syria."

Analysis by Frank Gardner, BBC security correspondent

Hussain's activities made him a key target for the US military, who included him at number three on a Pentagon "kill list" of IS leaders.

He became one of the most important western recruits for IS, playing a key role in radicalising and recruiting others to join the movement and plan attacks.

Whitehall officials have said in the past that his actions caused them great concern and his death would be "significant".

Hussain, a skilled computer hacker, was jailed for six months in 2012 for leaking former Prime Minister Tony Blair's private contacts online and making hoax calls to a counter-terror hotline.

In June, the Sun newspaper reported Hussain was also linked to an IS plot to detonate a bomb made with a pressure-cooker at an Armed Forces Day parade in London.

Hussain was married to former punk musician, Sally Jones, and was a known member of a computer hacking group called Team Poison.

The group has claimed responsibility for more than 1,400 offences where personal and private information has been illegally extracted from victims in the UK and around the world.

It claimed to be behind online hacking attacks involving foreign politicians, major international businesses, and an international humanitarian agency.

US officials say the drone strike that killed Hussain took place near to the city of Raqqa.

Security officials in the UK estimate about 700 Britons have travelled to Syria, and about half have since returned home.

Tracking Britain's jihadists

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