The Islamic State of Iraq and the Levant (ISIL) group has been taking control of parts of Syria and Iraq and has been threatening to kill all those who refuse to join its jihad.
Thousands of migrants and refugees have crossed into Europe from Iraq and Syria in recent months as the region has been torn apart by the war.
Many have been caught up in the conflict, which has displaced an estimated 8 million people.
The number of asylum applications by migrants from countries including Syria, Iraq and Afghanistan has more than doubled in the past year to over 200,000, according to the UN Refugee Agency.
A group of Muslim migrants in Romania said they were desperate to escape their war-torn country.
They are trying to get to Europe and have not reached any safe place.
They are afraid of what they have become,” said one of the migrants, who gave his name as Sibyl.”
I have no money and no place to stay, so I’m just hoping that I will get into the UK.
If I don’t, I can’t leave.
“Another migrant from the UK said he had been forced to go into hiding in his country for fear of being caught by ISIL.
He told the BBC: “The government has made me take the risk of hiding.
I don`t know if it`s good for my health.
If we were safe in the UK, I would not be forced to hide.
“It`s not just me, but thousands of other people.
I have no idea how they could smuggle us into the EU, and we are very scared.”
More than 5 million refugees have arrived in Europe since 2015, according a UN report.
The International Organization for Migration said the number of refugees who have fled to neighbouring countries had increased by more than 80% in the first three months of 2018, a rise that could worsen as the war rages.