Religious leaders are calling on British Muslims not to travel to Syria and Iraq, amid ongoing fears people are leaving the country to take part in fighting.
Over 100 imams from across major theological backgrounds and cultural groups have signed an open letter urging British Muslim communities "to continue the generous and tireless effort to support all of those affected by the crisis in Syria and unfolding events in Iraq", but to do so "from the UK in a safe and responsible way".
The open letter comes during the Islamic festival of Ramadan and as concerns have been raised about home-grown involvement in terrorism, after Britons appeared in a propaganda video for insurgent group Isis.
Security services believe an estimated 500 Britons have left the country to fight in Syria, according to the BBC.
Among them was Aseel Muthana, who told the BBC that he was fighting in Syria and had no intention of returning to the UK.
His brother Nasser appeared with two other British men - 20-year-old Reyaad Khan, from Cardiff, and Abdul Raqib Amin, who grew up in Aberdeen - in an Isis propaganda video.
The letter reads: "As the crisis in Syria and Iraq deepens, we the under-signed have come together as a unified voice to urge the British Muslim communities not to fall prey to any form of sectarian divisions or social discord.
"Ramadan, the month of mercy, teaches us the value of unity and perseverance and we urge the British Muslim communities to continue the generous and tireless efforts to support all of those affected by the crisis in Syria and unfolding events in Iraq, but to do so from the UK in a safe and responsible way."
In April, the Met also issued a plea calling for people to come forward with information about their family members if they were concerned about them joining terrorist training camps in Syria.
Qari Mohammed Asim, imam at Leeds Makka Mosque, who played a key role in organising the letter, said: "The scale of the humanitarian disaster in Syria and the escalating violence in Iraq calls for an unprecedented response.
"As we near the end of the first week of Ramadan our message is simple, we have come together to urge British Muslim communities not to fall prey to any form of sectarian divisions or social discord.
Additional reporting by Press Association