Fifteen oil workers, most of them from the Indian subcontinent, were killed Sunday in a head-on collision between two buses in southern Kuwait, officials said.

Seven of those killed were Indian nationals, five were Egyptians and the other three from Pakistan, said Mohammed al-Basri of the state-owned Kuwait Oil Company (KOC).

Two Indian citizens -- one in critical condition -- and a Kuwaiti were also injured in the accident, Basri told AFP.

Fire department spokesman Colonel Khalil al-Amir said the victims were employees of Burgan Drilling, a private subcontractor for KOC.

Like the other Arab states of the oil-rich Gulf, Kuwait has drawn international condemnation for its track record on migrant workers' rights and labor conditions.