Thai law enforcement authorities announced Thursday that they will file murder charges against former Prime Minister Abhisit Vejjajiva and his deputy in the first prosecutions of officials for their roles in a deadly 2010 crackdown on anti-government protests.

The protests and crackdown left more than 90 people dead and about 1,800 injured in Thailand's worst political violence in decades. Abhisit's Democrat Party, ousted in elections last year, and "red shirt" supporters of the ruling Pheu Thai Party have blamed each other for the bloodshed since.

Department of Special Investigation chief Tharit Phengdit said Thursday that investigators found Abhisit possibly culpable in the death of a taxi driver because he allowed troops to use war weapons and live ammunition against protesters.