Bulgarian police have detained a man after he pointed a gas pistol at an ethnic Turkish party leader delivering a speech at a party caucus in the capital.

No shots were fired from the self-defence device, which is not lethal but can cause serious injuries if fired at close range.

The video from the Saturday event in Sofia shows the man climbing the podium where Ahmed Dogan, the leader of the Movement for Rights and Freedoms, was speaking, and pointing the gun to his face.

Dogan struck the man before he could pull the trigger, while other delegates wrestled the assailant to the ground. TV footage showed several people punching, kicking and stomping on the man when he was on the ground.