KAMPALA, Uganda — Two senior Ugandan police officers were charged Friday over the mysterious kidnapping of a Rwandan refugee who had been a member of his country’s presidential guard.

Joel Aguma and Nixon Karuhanga appeared before a military court-martial in the capital, Kampala. They were charged alongside five junior police officers as well as a Congolese national and a Rwandan man. Their attorney disputed the charges.

Aguma leads the police’s professional standards unit and Karuhanga once led a special operations unit.

Their victim, Lt. Joel Mutabazi, was a member of Rwanda’s presidential guard before he fled to Uganda, where he won refugee status and was known to Ugandan and U.N. refugee officials.

According to the charge sheet, the suspects used firearms and grenades to kidnap Mutabazi before illegally handing him over to Rwanda’s government in October 2013. Mutabazi is now serving a life term after being convicted of plotting against his government.

It is not clear why the Ugandan police officers are being charged now, although Uganda’s president urged a purge of “criminal” officers after the murder in March of a senior policeman, Felix Kaweesi.

The case against the police officers is being closely followed in Uganda because the suspects are seen as allies of the police chief, Gen. Kale Kayihura.

Caleb Alaka, the suspects’ attorney, said his clients were tortured by military interrogators who wanted them to implicate Kayihura in the kidnapping.

“Some have terrible scars,” he said.

It was not possible to get a comment from Kayihura.