Deby's action, announced in a decree, came after the anti-corruption authority said its inspectors had been detained and assaulted by state security agents during a visit to audit SHT's operations earlier this month.
The decree did not give any reasons for Deby's actions, or mention the reported assault or detention.
The anti-corruption authority said in a statement last Wednesday its officers were assaulted after they requested documents to check revenues, including sales invoices sent to commodities trader Glencore (GLEN.L), opens new tab.
Glencore, which was not accused of any wrongdoing by the authority or any other body, declined to comment.
The national hydrocarbons company, in a statement published on Thursday, denied that it had deliberately obstructed the audit.
The president appointed a new inspector general and deputy inspector general at the anti-corruption authority, replacing the two former post-holders, according to the decree signed on Friday.
Chad ranks 157 out of 182 countries on Transparency International's Corruption Perceptions Index.
-Reuters









