What happens now that IS bride has had her baby in Syria?

Shamima Begum, 19, who left Bethnal Green in 2015 with friends to join the extremist group IS, has given birth to a baby boy in Syria.

She has said she wants to come back to the UK, but has pleaded not to be separated from the child if she returns.

:: What happened when she left?

When she and her friends sneaked out of the country, they sparked a counter-terrorism investigation.

However, the then head of Scotland Yard Bernard Hogan-Howe said in 2015 that Shamima Begum and her friends would not face terrorism charges if they returned - unless there was evidence they committed any specific crimes while with IS.

Mr Hogan-Howe's comments remain true, according to the lawyer representing her family.

Tasnime Akunjee confirmed to Sky News that he believes she should be treated as a victim, as long as no evidence of further offences while she has been abroad is found.

"I am relieved that she is alive and simultaneously appalled by the news that someone so young has birthed and lost children," Mr Akunjee said.

"There are many possibilities [regarding] her return," he said, without wanting to go into further detail out of respect to Shamima's family.

He added that the topic of Shamima Begum's return is "a contentious issue and stirs up very strong positions from the public", noting that he had already seen "some horrific comments".

Mr Akunjee continued: "There is a very traumatised young person who will have to live through the rest of her life with the added burden of the reporting of her tragedy."

:: How could Shamima Begum return?

She could either try to sneak back into the country from the refugee camp she is in, although this seems less of a possibility now given the publicity around her case, or seek assistance from the British authorities.

Her family has called upon the UK government to help bring her home.

However, she could face a temporary exclusion order, preventing her from entering the UK for a period and enabling her return to be managed.

Introduced in 2015, such orders can last for up to two years and can be imposed on those suspected of involvement in terrorism abroad.

Enforced by cancelling travel documents and through watch lists, this measure also allows for the imposition of certain measures on an individual once they do arrive back.

The powers were unused in 2016, while nine TEOs were issued in 2017.

:: What would happen if she finds a route back to the UK?

She will almost certainly face an investigation into whether she has committed any criminal offences and establish if she poses a threat.

The ultimate decision would rest with the home secretary, aided by assessments from MI5, MI6 and counter-terrorism police.

Security minister Ben Wallace said: "The UK advises against all travel to Syria and parts of Iraq. Anyone who does travel to these areas, for whatever reason, is putting themselves in considerable danger.

"Everyone who returns from taking part in the conflict in Syria or Iraq must expect to be investigated by the police to determine if they have committed criminal offences, and to ensure that they do not pose a threat to our national security.

"There are a range of terrorism offences where individuals can be convicted for crimes committed overseas and we can also use temporary exclusion orders to control an individual's return to the UK."

Estimates suggest 850 Britons, including around 150 women, have joined jihadist groups in Syria and Iraq.

Figures vary, but it is thought around 80 women and children have returned.

Women and girls returning from IS strongholds have been held in detention and questioned when they landed back on British soil.

:: How could the baby travel?

In most cases, a child born to a British mother abroad is considered to be British.

Under normal circumstances, the baby's family could get a passport or travel certificate from the British embassy of the country the baby was born in and be able to return to the UK.

However, the embassy in Damascus says all of its operations have been suspended and all diplomatic personnel have been withdrawn.

It is unclear whether the Home Office would intervene to make special arrangements for the child's return to the UK.

Culture Secretary Jeremy Wright, who previously served as attorney general, he said the nationality of Shamima Begum's baby was a "difficult question", and added that "we do have to be concerned about the health of that baby, we have to be concerned about her health too."

He said: "But in the end she will have to answer for her actions. So I think it is right that if she's able to come back to the UK that she does so but if she does so she will do it on the understanding that we can hold her to account for her behaviour thus far."

The Home Secretary Sajid Javid has said that he would do everything in his power to block Shamima Begum's re-entry to Britain.

At least one IS widow has had her baby taken away after returning to British soil.

:: How likely is it that she will be convicted of terrorism?

The chance of her being convicted of terrorism is slim, as the onus for prosecutors to prove terrorist activity took place beyond reasonable doubt is difficult because access to evidence is limited.

Figures disclosed in the Commons last year suggested that only around one in 10 returnees has been prosecuted over "direct action" in Syria, although ministers say a significant proportion of those who have come back were assessed as no longer being of national security concern.

Speaking in 2015 about Shamima Begum's case, Sir Mark Rowley, who is now retiring as the Met's head of counter-terrorism, said: "We have no evidence that these three girls are responsible for any terrorist offences. They have no reason to fear, if nothing else comes to light, that we will treat them as terrorists."

Mr Rowley's comments in theory protect her from facing jail time for being a member of IS, which has been a proscribed organisation since 2014 - the year before his comments. This carries a sentence of up to six months in jail and a fine.

A new law which was recently passed by parliament made it an offence to enter or remain in overseas terror hotspots, officially termed "designated areas". Those found guilty face up to 10 years in jail.

However, there are exemptions in the legislation which could apply to the teenager.

For instance, an offence is not committed if someone was already in an area on the day it was designated or leaves it within one month of it being flagged.

Given it only officially became law on 12 February, the timing in this case could prove critical.

Shamima Begum is believed to only have British nationality and so is protected from being stripped of her citizenship as this would render her stateless, which is not permitted under international law.

:: What other options are open to the authorities?

Under so-called terrorism prevention and investigation measures (TPIMs), the home secretary can impose a range of measures on individuals who are suspected of posing a threat to security, but who cannot be prosecuted.

Restrictions can include relocation to another part of the country, electronic monitoring and limits on the use of phones and computers. Latest figures show six TPIMs were in force.

There is also the government's anti-extremism programme known as Prevent, which aims to divert people away from terrorism.

However, the scheme has faced criticism and in the face of pressure, ministers announced earlier this year it would be independently reviewed.

What do the politicians and experts say about returnees?

Their opinion on those returning from IS is divided.

Defence Secretary Gavin Williamson previously said "a dead terrorist can't cause any harm to Britain".

Home Secretary Sajid Javid has warned he "will not hesitate" to prevent the return of Britons who travelled to join IS, arguing they were "full of hate for our country".

However, Justice Secretary David Gauke has conceded the government may not be able to stop returnees like Shamima Begum coming back to the UK as it "can't make people stateless".

The head of MI6 Alex Younger has warned those coming back to the UK were "potentially very dangerous" because someone who had been in "that sort of position" was likely to have acquired certain "skills or connections".

As such they would need a "very significant level of resource" to "make sure they don't represent a threat", he said.

Mark Hill, the UK's independent reviewer of terrorism legislation, has suggested authorities should look to rehabilitate rather than prosecute some British citizens who were coerced to join IS or who travelled to Syria and Iraq through "naivety".

Mr Hill added that those who return can represent an opportunity for the security services to gather intelligence.

Dr Katherine Brown, lecturer in Islamic Studies at the University of Birmingham, said there are a number of different fates facing returnees.

The option Shamima Begum is seeking, to return home, will see her be subject to the rule of the UK's legal system.

However, Dr Brown, writing in a blog about the ethical and practical responsibilities of returning foreign fighters, said: "There are challenges with this option because of questions about sufficient evidence, jurisdiction, and ambiguity about returnees' status."

She added: "Some may have been compelled to travel (often wives and children), and others may have supported [IS] through non-violent means...These should be matters for the police and courts to determine, not politicians or the media."

Dr Brown suggests this option is better than allowing returnees to face justice in the countries they are returning from.

She argues that although "we cannot eliminate the risk of terrorist behaviour entirely" by allowing them to return to the UK, "we can reduce that risk" and challenge "the extremist belief that the West doesn't care about Muslim citizens".