A former Irish soldier who once worked on the official plane of the Irish Taoiseach has been captured by US-backed forces in Syria under suspicion of joining Isil.

Lisa Smith, a 37-year-old woman from Dundalk, was a member of the Irish Defence Force until 2011 but quit after converting to Islam and then moved to Syria in 2015 following the collapse of her marriage, according to Irish media reports.

She is reported to have been detained along with her two-year-old son by forces in northern Syria in recent days as US-backed Syrian Democratic Forces close in on the last scraps of territory held by the Islamic State of Iraq and the Levant (Isil).

Members of Ms Smith’s family told the Irish Independent newspaper that Ms Smith had got in touch last month asking for money to aid her escape to Turkey, prompting them to reach out to the Irish government for help. “I just want to get her home,” the relative said.

The relative also identified Ms Smith to Irish police as the woman interviewed in Syria by ITV News on March 3 who had spoken with an Irish accent but claimed to be British, her face hidden by a niqab.