Iran's envoy to Turkey was evacuated from the embassy in Ankara on Monday after a warning of a possible bomb threat, local media reported.
The mission in the Turkish capital had been given an intelligence warning of a possible suicide bomb attack, DHA news agency reported, without giving further details.
Police conducted searches of cars close to the embassy after the road was shut off, an AFP photographer said.
Turkey was hit by a series of terror attacks in 2015 and 2016 blamed on Kurdish militants and the militant Islamic State (IS) group.
The last attack blamed on IS was in January 2017 when a gunman killed 39 people at an elite Istanbul nightclub during New Year celebrations.
Since then, Turkish police have conducted regular raids across the country against suspected members of the outlawed Kurdistan Workers' Party (PKK) and IS.
The PKK is blacklisted as a terrorist organisation by Ankara and its' Western allies.