Lisa Smith, 38, moved to Syria in 2015 to live under Isis rule after converting to Islam

A former member of the Irish defence forces who moved to Syria to live under Islamic State has returned to Ireland and been arrested on suspicion of terrorist offences.

Police met Lisa Smith upon her arrival in Dublin on Sunday on a Turkish Airlines flight from Istanbul and took her away for questioning. The former soldier, 38, flew from Turkey with her two-year-old daughter plus three Irish consular officials, members of the Army Ranger Wing and a Turkish security officer.

Smith, from Dundalk in County Louth, converted to Islam about a decade ago and travelled to Syria in 2015 to live in Isis’s self-declared caliphate. She married and had a child with a British jihadist, Sajid Aslam, whom she said later died in the conflict.

After the terror group’s defeat this year, Smith and her daughter stayed in refugee camps run by Kurdish forces. After Turkey invaded last month an Ankara-backed militia handed the pair to Turkey, leading to negotiations with Irish officials for her repatriation.

Irish authorities want to determine whether Smith committed terrorist acts. She is being questioned at a Garda station in south Dublin under section 30 of the Offences Against the State Act.

“This is a sensitive case and I want to reassure people that all relevant state agencies are closely involved,” the justice minister, Charlie Flanagan, said in a statement. “A multi-agency network is in place here comprising agency personnel who engage on an ongoing basis with international colleagues regarding emerging practice in relation to the complex issue of radicalisation.”

Smith has admitted sympathising with Isis but denies taking up arms. In media interviews before her repatriation she said a spiritual yearning led her to a mosque in Dundalk and subsequent radicalisation by a US extremist she met on Facebook.

“I was looking for answers … I was very depressed in life. I didn’t want to live any more. I was one of these people that was like suicidal, you know, because there’s no answers,” she told the Irish Independent in April.

Smith was a private in the defence forces before transferring to the Air Corps where she served as a flight attendant on a government jet during Bertie Ahern’s tenure as taoiseach. She left the defence forces in 2011.

Politicians and commentators have debated whether Smith’s stated wish to return to Ireland should be granted.

The taoiseach, Leo Varadkar, said mother and daughter, both Irish citizens, should be allowed home but that security assessments would be needed to ensure Smith “does not become a threat to life and limb in Ireland”. Smith’s relatives are caring for her daughter.