The father of a Jordanian pilot captured by the self-proclaimed Islamic State group in Syria has appealed to the militants to treat his son well.

26-year-old 1st Lieutenant Mu’ath al-Kasasbeh was taken prisoner after his warplane came down on December 24.

Speaking as a delegation of senior Christian leaders visited the family to express their solidarity, Safi al-Kasasbeh said:

“I call on the brothers from ISIL to consider him their son and their colleague in prayer to treat him well and consider him as their son and a guest on this, the anniversary of the birth of the Prophet Mohammad.”

The pilot’s plane crashed in a rural area of Raqqa province, an ISIL stronghold in northeastern Syria, while carrying out airstrikes against militant targets.

Jordan, one of several Arab countries involved in the US-led coalition, has not confirmed ISIL’s claims that the jet was shot down.

The extremist group released what it said was an interview with the pilot in which he said a missile had shot down his jet. The interview has not been verified.

Some reports say US forces carried out a failed mission to rescue the pilot on New Year’s Day.

The young man is said by a family friend to be a devout Muslim who felt it was his religious duty to fight extremist groups like the so-called Islamic State who were “distorting the true spirit of Islam”.