US embassy in Turkey resumes service after 'security threat'

The US Embassy in Turkey says it is preparing to resume regular services after a security threat forced it to close for a day.

The embassy in Ankara was closed on Monday as police in the Turkish Black Sea coastal city of Samsun detained four Islamic State group suspects while investigating a possible attack plot involving the American facility.

Only limited services were provided on Tuesday, but spokesman David Gainer says the embassy "will be operating as normal" on Wednesday.

Police had stepped up security, searching pedestrians before allowing them to enter the street where the US Embassy and other buildings are located.

In 2013, a suicide bomber detonated an explosive in front of the embassy, killing himself and a Turkish guard.

Turkish police have carried out a number of raids against suspected IS cells in the country, including swoops that saw 29 foreigners detained over alleged links to the group.

Relations between Turkey and the US have been strained following Washington's support for the Kurdish People's Protection Units (YPG) militia, which has been heavily involved the war against IS in Syria.

Ankara views the YPG as a terror group and linked to the Kurdistan Workers' Party who have launched numerous attacks in Turkey.