* Dismissals follow firing of police chief
* Review commission said to have found irregularities
* Oil-producing state hamstrung by graft, instability
N'DJAMENA, Feb 15 (Reuters) - Chadian President Idriss Deby fired two ministers in charge of security after his suspension last week of the central African nation's entire nearly 6,000-member police force following allegations of graft, favouritism and abuse.
In an announcement read over state radio late on Thursday, Deby sacked Public Security Minister Ahmat Mahamat Bachir, and Bachar Ali Souleymane, minister of territorial administration.
The dismissals followed the firing of Chad's police chief on Feb. 6, two days after the suspension of the force itself.
"The two ministers are guilty of favouritism during the police recruitment process. They hired people with little competence and promoted them within the police," a member of the commission carrying out a review of the force on Deby's orders told Reuters. He asked not to be named.
The commission had uncovered widespread irregularities in the police force, whose duties since its suspension, including public safety patrols and traffic control, were being carried out by paramilitary gendarmes, the source said.
The security shake-up was taking place in the oil-producing country at a time when hundreds of its soldiers led by Deby's son were helping French and Malian forces to hunt Islamist insurgents in Mali, further to the west on the continent.
Chad's president had given the review commission a month to check every member of the police force and ensure each was hired according to the rules, and for specific jobs.
Chad has produced oil for nearly a decade but the land-locked country's economy has been hamstrung for years by graft and instability.
In February last year, Deby sacked the minister for morality and good governance after he was charged with corruption. He was accused of stealing hundreds of thousands of dollars meant to fund efforts to fight graft. (Reporting by Madjiasra Nako; Writing by Bate Felix; Editing by Pascal Fletcher and Michael Roddy)