ISIS is planning to send members of its feared all-female police force to attack religious sites in Europe, a Syrian expert claims.

The terror group will send at least ten members of the ruthless Al-Khansaa Brigade to target 'Christian symbols', possibly in suicide bomb attacks, the president of the Centre for Strategy, Military and Security Studies in Syria told MailOnline.

As many as 60 British women are thought to be members of the brigade and they are paid around £100 a month.

The militants patrol the city with AK47s, mercilessly beat women who step out of line and even force some into becoming sex slaves.

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Threat: ISIS plans to send women from its all-female 'Gestapo', the Al-Khansaa Brigade, to attack religious sites in Europe

Rare images of the female militants show them covered head-to-toe in black burkas but they will enter Europe dressed as tourists so they do not draw attention, according to Fahad Al-Masri.

Before taking up his current role, Al-Masri was a spokesman for the Free Syrian Army (FSA) rebel group who battled both ISIS and government of President Bashar Al-Assad during the country's civil war.

He has appeared on international TV stations like Sky News Arabia where he aggressively urged all foreign jihadists to 'get out of Syria' in a 2013 interview. He was fired by the FSA shortly after the interview because the group said he did not represent its views.

Citing his sources inside ISIS-held territory in Syria, who cannot be named for safety reasons, Al-Masri said: 'This is the first time women will be used in these operations. It will be a surprise for the European authorities who look for men.

'Women are not as difficult as men to sneak into countries and there are many European women in the Al-Khansaa Brigade – like French and British – which makes it easier for them to get in undetected.

'We don't think the women will be wearing a hijab or burka – so they do not stand out. They will be normal like everybody, as if they are tourists.'

Among the dozens of British women who have joined the brigade is Aqsa Mahmood from Glasgow, who is thought to have reached a senior position in its ranks.

The three Bethnal Green schoolgirls who joined ISIS - two of whom have since been married off to militants - were also feared to have joined the brigade.

Covert: Its fanatical members (file photo) will enter Europe dressed as tourists, the president of the Centre for Strategy, Military and Security Studies in Syria told MailOnline

Fanatics: It was feared that Amira Abase (left), Kadiza Sultana (centre) and Shamima Begum (right) had joined the fearsome Al-Khansaa Brigade

Some experts believe the Sunni extremists have targeted Shi'ite Muslims in Iraq and Syria to spark a sectarian war between the two sects of Islam.

After analysing the information his secret sources have given him, Al-Masri says ISIS may be trying to do the same against the West.

He said: 'The next operations for ISIS in Europe will be against Christians... In the Middle East, it's mainly been Sunni against Shi'ite Muslims, but now ISIS wants to create a conflict between Christians and Muslims.

'That means ISIS will try and attack Christian symbols in Europe – like the Vatican for example.'

European nations are not the only ones in danger. ISIS also plans to send the female fanatics to attack African nations and Arab countries like UAE, Kuwait, Jordan and Turkey also, Al-Masri's sources told him.

ISIS wants to create a conflict between Christians and Muslims... That means ISIS will try and attack Christian symbols in Europe – like the Vatican for example Fahad Al-Masri, president of the Centre for Strategy, Military and Security Studies

But security analysts told MailOnline the claims are 'far-fetched' because intelligence agencies are tracking both male and female jihadis, security is very high in European countries following recent terror attacks such as the one in Tunisia and there is no evidence of the male-dominated terror group ever using women to carry out attacks.

Raffaello Pantucci from counter-terrorism think-tank RUSI told said: 'These women would have the same difficulties as anyone else trying to launch an attack.

'Who would you send? You would have to send someone you know had not been noticed by security services before - because they know women as well as men are traveling so they're watching out for both.

'You would have to sneak past a very high level of security and in some countries that might be doable but if you try and get into a country like the UK, it would be incredibly difficult.

'Why would such a chauvinist society send women back to carry out attacks? There is no evidence of them every using women before so there's no reason for them to start now.'

In May, MailOnline uncovered ISIS marriage certificates that suggested the jihadi group would begin to use women to carry out suicide attacks.

Written in Arabic and signed by both husband and wife, the document stated the final decision over her life – and death – rested with ISIS leader Abu Bakr Al-Baghdadi.

Under 'conditions of wife' it said: 'If the Prince of believers [Baghdadi] consents to her carrying out a suicide mission, then her husband should not prohibit her.'

Heartless: The ruthless women (file photo) patrol Raqqa with AK47s, mercilessly beat women who step out of line and even force some into becoming sex slaves

It confirmed Islamic State were forcing women to the battle-front to replace the countless male fighters being slain in bloody battles across Iraq and Syria, counter-terrorism experts told MailOnline.

In raqqa, ISIS's de facto capital, Al-Khansaa women operate undercover, mingling into crowds to listen out for dissent and they run brothels where kidnapped girls are expected to 'satisfy' fighters returning from battle, according to Channel 4 documentary, 'Escape From ISIS'.

Abducted women and girls are supposedly taken to Raqqa and imprisoned as sex slaves. Some of those who miraculously escaped claimed they were made to sleep with hundreds of different fighters in just a few weeks.

A former Al-Khansaa enforcer, Umm Abaid, told the filmmakers how she led a normal life until ISIS stormed into Raqqa and imposed its strict interpretation of Sharia law.

She said: 'I went to school, to coffee shops... but slowly, slowly my husband [a Saudi Arabian ISIS fighter killed in a suicide bomb attack] convinced me about Islamic State and its ideas. I joined the brigade and was responsible for enforcing the clothing regulations.

'Anyone who broke the rules, we would lash. Then we would take her male guardian, her brother, father or husband, and lash him, too.

Agreement: A wedding document discovered in May (pictured), which states a husband can not stop his wife going on suicide missions, suggested ISIS would start using women to carry out their depraved attacks

'Even when I was off duty, if I was with my husband in the car and we saw a woman dressed wrong, he would stop and tell me to deal with her.

'I remember one woman walking with her husband wearing a robe with images on it. We arrested her and took her to the Al-Khansaa base. I lashed her with my own hands.'

Umm Abaid escaped to Turkey after ISIS extremists tried to force her to remarry just weeks after her husband blew himself up in a suicide bombing.

Even girls who have gone willingly to Raqqa - thinking they were going to marry one fighter - have found they are expected to spend a week with their new 'spouse' before they are 'divorced' by an Islamic cleric and married to another fighter for a week.