Alfred Paolo Conteh was detained along with Sannah Marrah, the defence ministry's former director general, at the Criminal Investigation Department on Friday. Both are awaiting charges, the Sierra Leone Anti Corruption Commission said.

The commission said officials are investigating allegations of corruption over procurement of military vehicles, uniforms and rice in 2015. The procurement contract was reported to be worth $10 million.

"We are recovering monies stolen from our people," anti-corruption commissioner Joseph Ben Kelfalla told reporters in Freetown, adding that authorities had recovered more than one million dollars from corrupt officials.

Most of the military supply deals were done in China, according to a report published in 2015 by the Sierra Leone audit services that identified flaws in procurement procedures.

President Julius Maada Bio took office in early April after a tumultuous election campaign in which he targeted corruption, ending a decade-long rule by the All People's Congress (APC).

Soon after he took office a report commissioned by the new government charged that "rampant corruption" in the former administration had led to the "near collapse" of the West African nation's economy.

The government has approved a commission of enquiry, with hearings expected to begin in January 2019.

Several former government ministers including the ex-vice president Victor Bockarie Foh have been arrested this year on corruption allegations.

The APC has slammed the probe, calling it a "witch hunt" and vowing not to cooperate with the commission of enquiry.

"The government will not tolerate any intimidation, indiscipline and incitement from any political party," a senior official at the Ministry of Information and Communication told AFP.

"The fight against corruption will continue and the commission of enquiry will commence in January," the senior government official said.

One of the world's poorest nations despite huge mineral and diamond deposits, Sierra Leone's fragile economy is still recovering from war and disease, including a 2014 Ebola epidemic.