The mother of a medical student from Hounslow believed to have been abducted in Ukraine has said she is 'very concerned' about his well-being.
Mohammed Elgasim, of Sutton Dene, Hounslow, is understood to have been on his way to rent a flat in Donetsk when he was snatched from the streets by militants.
His captors are thought to be representing the self-proclaimed Donetsk People's Republic, a separatist group seeking independence from Ukraine.
Photos of the 22-year-old's passport and student ID card were last Thursday (July 31) posted on Facebook, along with a post claiming two 'mercenaries' had been captured.
The post said: "According to their fake story, the Sudanese 'students' have moved from Sudan to London, where they received British citizenship, and then went for studies to the Donbass.
"No documents certifying studying at the detainees weren't found. Both persons are transferred to the security department of Donetsk republic. These 2 could be spies and artillery gunner for Kiev junta."
Mohammed's parents became worried when he failed to get in touch for Eid al-Fitr, the Muslim festival marking the end of Ramadan, last Monday (July 28).
His mother Hounida Osman today told getwestlondon she remained 'very concerned' about her son's well-being but did not want to comment further at this stage.
Ukraine appears to be on the brink of civil war. Crimea declared independence earlier this year in a vote not recognised by the Ukrainian government, and fighting is now reported to be spreading towards Donetsk, near the Russian border.
A spokesman for the Foreign and Commonwealth Office said: "We are aware that a British national has been reported missing, and possibly detained, in Donetsk. We are providing consular assistance to the family at this distressing time.
"We are liaising closely with the OSCE (Organization for Security and Co-operation in Europe) and the authorities in Moscow and Kyiv about these reports and are working closely with them to establish the facts."