'I call upon any brother to take up a knife and kill as they did #colchester': British ISIS fighter who threatens to come back to UK urges British Muslims to avenge murder of Saudi woman in Essex
- Abu Rashash Britani claims to be a British Muslim fighting for ISIS in Syria
- He called for revenge attacks in the UK following murder of Nahid Almanea
- She was killed in Colchester on Tuesday, possibly for wearing Muslim dress
- Police are already investigating claims made by Abu Rashash on Twitter
- He previously said ISIS has ordered Britons fighting in Syria to return to UK
- It is thought highly-trained fighters may return to carry out attacks at home
Twitter has since suspended the account used by Abu Rashash Britani
A man using the nom de guerre Abu Rashash Britani has previously claimed that he and other British insurgents have been ordered to return to Britain once they have finished fighting in Iraq and Syria by the fanatical ISIS leader Abu Bakr al-Baghdadi.
Following the murder of 31-year-old PHD student Nahid Almanea in Colchester, Essex on Tuesday, Abu Rashash Britani said: 'I call upon any brother to take up a knife and kill as they did #colchester'.
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Jihadist: Abu Rashash Britani (picture taken from his Twitter account) has previously claimed that he and other British insurgents have been ordered to return home once they have finished fighting in Iraq and Syria
Following the murder of 32-year-old PHD student Nahid Al Manea in Colchester yesterday, Abu Rashash Britani urged Muslims to carry out revenge attacks
Abu Rashash Britani took to Twitter to express anger over the murder of PHD student Nahid Al Manea
A previous tweet by Abu Rashash suggests Abu Bakr al-Baghdadi, head of ISIS, will target the UK with homegrown fighters
Baghdadi, who has a £6million bounty on his head, is considered the world's most dangerous terrorist leader.
Now, following the murder of a Saudi woman of Ms Almanea in Colchester - which police believed may have been inspired by her conservative Muslim clothing - Abu Rashash Britani called for revenge attacks.
'These kuffar getting out of hand, dare they touch a #Muslimah. I call upon any brother to take up a knife and kill as they did #colchester,' he posted on Twitter.
Drawing comparisons to the murder of Drummer Lee Rigby outside his barracks in Greenwich last year, the ISIS fighter added: '#colchester attack is cowardly act. At least when our noble brothers, killers of #leerigby did so they killed a soldier not a civilian.'
Twitter has since suspended the account used by Abu Rashash Britani.
Nahid Almanea was found bleeding to death at 10.40am on Tuesday on a footpath in Colchester.
She was wearing a dark blue robe called an Abaya, as well as a multi-coloured hijab scarf, leading police to believe she may have been targeted for religious reasons.
A 52-year-old man from Colchester was arrested in connection with the incident. Officers are thought to have requested extra time to question him.
Murder hunt: Police have revealed the woman found battered to death in Colchester yesterday morning was wearing a full-length robe and a hijab as they investigate whether the attack was racially motivated
Probe: Police are appealing for anyone with information. It is the second brutal murder in Colchester since March
It was the first time it had been suggested that Baghdadi is preparing to send his battle-hardened and highly trained ISIS fighters back to the UK.
The revelation came as David Cameron warned that Britain cannot afford to ignore the chaos in Iraq and Syria because of the risk that British jihadis will bring their murderous tactics back to the UK.
He told MPs: 'I disagree with those people who think this is nothing to do with us and if they want to have some sort of extreme Islamist regime in the middle of Iraq, that won't affect us. It will.
'The people in that regime – as well as trying to take territory – are also planning to attack us here at home in the United Kingdom. So the right answer is to be long-term, hard-headed, patient and intelligent with the interventions that we make.'
Mr Cameron, who described the estimated 400 British fighters in the region as 'the most serious threat to Britain's security that there is today', later chaired a meeting of Britain's National Security Council.
In a statement, No 10 said British military intervention was 'not on the table'. Sources said the security services are focusing on the threat posed by returning foreign fighters.
Extremists: A picture posted on Twitter reportedly showing balaclava-clad British jihadists Abu Daigham al Britani and Abu Abdullah al Britani posing with a jihadist flag and brandishing machine guns
* Downing Street said 14 Britons have had their passports seized to stop them going to Syria to fight over the past year.
* A senior Tory MP called for Tony Blair to be impeached for misleading the Commons in the run-up to the 2003 invasion. Father of the House Sir Peter Tapsell said ancient Parliamentary powers should be revived to hold Mr Blair 'to account'.
* MI5 and Scotland Yard are monitoring the use of social media by British jihadists in Syria.
Abu Bakr al-Baghdadi, commander of the Islamic State in Iraq and the Levant, is shown in a U.S. State Department wanted poster
He is called the 'new Osama Bin Laden' but even Al Qaeda have distanced itself from his bloodstained methods and goals.
The identity of Abu Rashash Britani is not known, but he is thought to be linked to a group of eight Britons from London and Portsmouth operating as part of a unit called the British Kataa'ib, meaning British Brigades.
Britons in Syria are encouraging others in the UK to follow them by offering a rough travel guide for would-be jihadists.
In a series of postings, they advise people to travel light and bring a smartphone for internet access, but to leave religious books at home to avoid suspicion when travelling through airports.
They highlight the need for visas for those heading to Turkey, the main 'gateway' border to Syria, and even detail the type of plug adaptors new recruits will need to charge their electronic devices.
One Briton, who goes by the alias Abu Abdullah al-Britani, told would-be militants on the Ask.fm website to delete 'jihad pics' from their phones in case they are searched. He added: 'Be careful is my advice. I would delete them kinda things'.