Nearly 26,000 foreigners, including a member of the militant group ISIS, have been blocked from boarding flights to South Korea since the government introduced a passenger screening system last year, justice ministry data showed Wednesday.

The screening system, in effect since April last year, is designed to prevent the entry of terrorists, criminals and other dangerous foreigners before their departure for South Korea. The government screens them out after receiving passenger manifests from airlines.

A total of 25,598 foreigners were blocked from boarding flights to the country between April last year and August this year, according to justice ministry data submitted to Rep. Keum Tae-sup of the ruling Democratic Party for a parliamentary audit of the government.

That translates into an average of 1,506 people per month.

The blocked people include a 40-year-old ISIS member who attempted to board a flight to South Korea from an airport in the Kazakh city of Almaty in March, according to the data.

Fourteen were on Interpol's wanted list and 947 were holding passports listed in its database. About half of the total, 13,358, were blocked as they held passports that were nullified, stolen or canceled, according to the data.

A total of 1,621 were banned for crimes committed while previously staying in South Korea. (Yonhap)