Turkey's President Tayyip Erdogan makes a speech during the opening ceremony of newly built Yavuz Sultan Selim bridge, the third bridge over the Bosphorus linking the city's European and Asian sides in Istanbul, Turkey. REUTERS/Murad Sezer

ISTANBUL (Reuters) - Turkey has arrested 865 people since the start of 2016 in its fight against Islamic State, and more than half of those were foreigners, Interior Minister Efkan Ala said in remarks broadcast on Turkish television channels on Wednesday.

Thousands of foreign fighters from countries including Turkey, Britain, Europe and the United States have joined the Islamist militants in their self-proclaimed caliphate in recent years, many of them passing through Turkey. Turkey has since launched a crackdown on the networks facilitating their passage.

Since launching the crackdown, Turkey has detained a total of 5,803 people, of which about 2,200 were foreigners, the minister said, without giving a precise period.