Floodgates could be opened for Islamic State supporters coming back to the UK if Shamima Begum succeeds in getting back into the country, a former counter-terrorism police chief has warned.

Scott Wilson, who helped lead the response to the 2017 London Bridge attack, said monitoring the teenager would cost millions of pounds and the security services and police would “never be able to take their eye off her” if she did return.

Begum, who left her east London home to join IS in Syria in 2015, wants to return to the UK for the sake of her newborn third child, but has been stripped of her British citizenship.

Home Secretary Sajid Javid made the move on advice that she qualified for Bangladeshi citizenship through her mother, although authorities there have said they will not let her enter the country.

Mr Wilson, who was UK National Counter Terrorism Co-ordinator for Protect and Prepare until last summer, said: “When you look at all the background to her going out there, I know they are trying to say she was a groomed child, but there was a lot of planning that went in with her and her group to get herself out there.

“It’s not just the bringing her back, the deradicalisation programme; the security services will end up spending years monitoring her.

“They will never be able to take their eye off her for the simple reason that they don’t know what could happen. If she did do something in the UK, the Government and the security services would get the blame for it.

“It’s the millions of pounds of monitoring that it’s going to cause, not just the bringing her back and putting her through a deradicalisation programme.”

Last week, Oxford-born terror suspect Jack Letts, known as Jihadi Jack, said he wants to return to the UK, and misses his mother, pasties and Doctor Who.

It was also reported that Abu Hamza’s son, Sufyan Mustafa, 23, is fighting the decision to revoke his British passport.

Mr Wilson believes a slew of suspected IS supporters will want to return to the UK if Begum succeeds in doing so.

“I don’t think the British Government should give her the way to get her out of Syria and get her back here, that’s the point,” he said. “If she gets back here then it’s on their plate to deal with it.

“If you start making a free way for them to get back then where do you stop?

“I can see floodgates opening. I don’t think we should make it easy. If you make it easy then you’re just opening the floodgates for it and suddenly you’re monitoring people forever.

“I don’t sound very sympathetic because I just see the consequences. I dealt with London Bridge on the streets.

“When you see the consequences of this, I just think this country can be too sympathetic at times. She made the decision so she will have to stick to the decision she made.”

Begum’s father, Ahmed Ali, said his 19-year-old daughter should face justice in Britain despite previously appearing to back the removal of her citizenship.

The teenager, who married Dutch IS fighter Yago Riedijk, had two older children who both died.

Mr Ali told ITV News: “I don’t think he’s (Sajid Javid) done the right thing because she is a British citizen, and if it turns out she has committed any crimes, then she should face justice in the UK.

“She belongs to this country, she belongs to England.

“My daughter was a little child, she made a mistake, she didn’t properly understand.”

A stolen WWII gate bearing the infamous Nazi slogan.

Returning after two years to its home in Dachau, a former concentration camp in Germany.

It disappeared overnight in 2014 and only resurfaced in Norway in December after police followed an anonymous tip off.

The words “work sets you free” cast into this Iron Gate would have been one of the first things prisoners saw as they arrived, a symbol of the suffering they endured here.

On Sunday U.S. Vice President Mike Pence visited the site, its gas chambers, crematorium and old accommodation now serving as a memorial.

It was the first Nazi concentration camp, used as a prototype for what became a network of sites where millions were murdered.

In this camp alone there were 200,000 people by the time US troops liberated it in 1945.

Starved and diseased inmates and piles of bodies here became some of the first public images of the Holocaust atrocities.