A Japanese tourist was temporarily detained by the Kurdistan Regional Government after entering war-torn northern Iraq earlier this month, the Foreign Ministry announced late Saturday night in Tokyo.
The man, who has since returned to Japan, entered the city of Irbil, capital of Iraq's Kurdistan region, through Turkey on foot, the ministry said.
He was determined by regional authorities to be suspicious and was detained for a few days, according to the ministry. The man's name was not disclosed.
Diplomatic sources said the man was apparently in northern Iraq for sightseeing.
The Kurdish government, which is fiercely battling the Islamic State group, is stepping up surveillance of foreigners trying to enter Islamic State-controlled areas of Iraq and Syria through Turkey, the ministry cautioned.
It noted the tightened security on this occasion led to the arrest and temporary detention of the Japanese tourist.
The ministry is warning Japanese travelers against traveling to Irbil and surrounding areas.