Four female and five male British students are reported to be most likely working at hospitals controlled by ISIL extremists.

MOSCOW (Sputnik) – Four female and five male students have travelled illegally from the United Kingdom to Syria and are most likely working at hospitals controlled by ISIL extremists, the Observer reports.

"They have been cheated, brainwashed. That is what I, and their relatives, think," Turkish opposition politician Mehmet Ali Ediboglu told the Sunday British newspaper.

Shortly after talking to the students' families, Ediboglu told the Observer that both he and the parents were convinced that the group was set on working for ISIL.

"We all assume that they are in Tel Abyad now, which is under ISIS [ISIL] control. The conflict out there is fierce, so medical help must be needed," Ediboglu said, stressing that the students went to Syria "to help, not to fight."

According to the Observer, the students are in their late teens or early 20s and all of them have Sudanese roots but were born and raised in England. They crossed the Turkish-Syrian border last week. On Saturday, their families travelled to the area to persuade them to return home.

A British government source told the newspaper that the students would not automatically face prosecution if they come back to the United Kingdom, as long as they prove that they had not been involved in any fighting.

The Islamic State of Iraq and the Levant (ISIL), also known as the Islamic State of Iraq and Syria (ISIS), has captured vast areas in Syria and Iraq, having proclaimed the establishment of an Islamic caliphate on the territories under its control.

According to recent estimates by US intelligence officials, some 20,000 foreign fighters including 4,000 people from Western Europe have joined ISIL in the last three years.

Turkey has deported 1,500 European citizens trying to cross the border into Syria to join ISIL and other extremists, according to the Observer, which cites Turkey's Ministry for EU Affairs.