It happened in a flash.
A man Saturday approached Bulgarian opposition politician Ahmet Dogan, who was at a lectern giving a speech at a party conference in Sofia, the capital city.
Video shows the man pointing a gas pistol at the head of Dogan, who grappled with him, according to Bulgaria State News (BTA).
Dogan, leader of the ethnic Turk Movement for Rights and Freedoms (MRF), managed to knock the gun away as people rushed the stage and subdued the assailant.
The suspect was arrested and identified as Oktay Yenimehmedov, 25, according to media reports.
Dogan, who is leaving his party post after more than 20 years, was unscathed. He did not continue his speech.
BTA did not indicate a possible motive.
Turkey's Anadolu News Agency said the majority of MRF's members are ethnic Turks, who make up nearly 9% of Bulgaria's population.
The convention elected Lutfi Mestan to succeed Dogan, Anadolu reported.