03/25/2015 07:49 EDT | Updated 05/25/2015 05:59 EDT

Parents of missing medical students in Turkey won't leave without children

There are seven families and a sad hum in a hotel lobby in southeastern Turkey near the Syrian border. The space is a makeshift headquarters, a command centre in their search for their children.

The people there are the parents of some of the 11 young people, ranging in age from 19 to their late 20s, who arrived in Turkey on March 12 and are believed to have crossed into Syria on March 13 or 14. Their intention was to offer medical help to refugees.

There is concern now that the group is offering medical aid in territory controlled by Islamic State in Iraq and Syria (ISIS).

In a joint statement, the families say they believe their children came to Turkey "willingly to offer voluntary medical help to those refugees who are in need of medical care on Turkey’s borders.”

One is a Canadian citizen — Ismail Hamdoun. He studied at the University of Toronto and, like the other missing young people, studied medicine in Sudan.

Successful in school

The others hold Sudanese, American and British citizenship.

Their missing young people, the parents say, have always been successful in school and in their social lives.

Hamdoun’s father, Ibrahim, a small business owner currently living in New Jersey, is among the parents in Turkey hoping to leave with their children. He arrived in Turkey March 18.

“I just want my son," he told CBC News. "That’s the only thing I want.”

None of the families wanted to be recorded, and for security reasons, their location is not being named.

Late into the evening, the parents are huddled in small groups on sofas throughout the lobby. They all clutch their mobile phones, looking for messages from their children.

No communication

A Turkish opposition MP trying to help the families said some have received text messages from their children saying that they are doing fine and are well taken care of, but that hasn't allayed any fears.

Hamdoun said he has not been able to communicate with his son.

He and the other parents are asking for the Turkish, British and Sudanese governments for help to get their children back.

Their statement says they've made "tremendous efforts" to find them on their own.

"We hope that the … governments of these countries would enforce, speed up and co-ordinate more effective measures to ensure the safety of our children wherever they are and bring them back to us as soon as possible."