ANKARA (Reuters) - A spy who worked for a country in the U.S.-led coalition that is fighting Islamic State had helped three British girls to cross into Syria to join the militants and has been caught, the Turkish foreign minister said on Thursday.

British teenage girls Shamima Begun, Amira Abase and Kadiza Sultana (L-R) walk through security at Gatwick airport before they boarded a flight to Turkey on February 17, 2015, in this combination picture made from handout still images taken from CCTV and released by the Metropolitan Police on February 22, 2015. REUTERS/Metropolitan Police/Handout via Reuters

The minister, Mevlut Cavusoglu, told broadcaster A Haber in an interview: “He was caught. It turned out to be someone who works for the intelligence of a country from the coalition.”

He didn’t say which country the spy was working for, but said it was not the European Union or the United States. The coalition also includes countries such as Saudi Arabia, Qatar, Jordan, Bahrain, Australia and Canada.

A European security source familiar with the case of the three girls said the person in question had a connection with the Canadian Security Intelligence Service (CSIS) spy agency.

A Canadian government source in Ottawa said the person was not a Canadian citizen and was not employed by CSIS. The source did not respond when asked whether the person had been working for CSIS.

The spy agency did not respond to requests for comment. The office of Public Safety Minister Steven Blaney - in overall charge of law enforcement - said it did not comment on operational matters.

A Turkish official who declined to be identified told Reuters the spy was now in custody.

“The person was working for the intelligence agency of a coalition country but is not a citizen of that country. The person was not a Turkish citizen either,” he said.

Islamic State seized large swathes of land last June, including territory close to the Turkish border. The U.S.-led coalition is using mostly air power in an attempt to push the Sunni militant group back.

British police and the girls’ families have issued appeals for their daughters to return home after they flew to Istanbul from London on Feb. 17. Amira Abase, 15, Shamima Begum, 15, and Kadiza Sultana, 16, are thought to have since entered Syrian territory controlled by Islamic State.

Thousands of foreigners from more than 80 nations, including Britain, other parts of Europe, China and the United States, have joined the ranks of Islamic State and other radical groups in Syria and Iraq, many crossing through Turkey.

Turkey says it needs more information from foreign intelligence agencies to intercept them.