Pakistan has charged a former police officer in last year's high-profile killing of a 27-year-old aspiring male model whose death triggered nationwide protests by members of his tribe.

Prosecutor Jabran Nasir says the former officer, Rao Anwar, pleaded not guilty at Monday's hearing. He says the trial will begin in April.

The aspiring model, Naqeeb Ullah, was killed under suspicious circumstances in January 2018 in what authorities initially described as shootout during a raid on a militant hideout in the southern port city of Karachi.

Following the shootout, Anwar and several other officers were arrested. At the time, Anwar claimed Ullah had links to militants.

A subsequent government probe concluded that Ullah, who hailed from the South Waziristan region, once a Taliban stronghold, had no ties to militants.