As well-heeled tourists sunbathed at the Maldives’ luxury resorts, efforts to report on extremism and corruption were violently countered in Malé, the densely populated capital. In the years since Mr. Abdulla’s abduction, newsrooms have been set ablaze by masked intruders or vandalized with a rusty machete. In 2016, the government passed a bill criminalizing defamation that critics argued would curb free speech.

Last year, Yameen Rasheed, a liberal blogger who wrote satirical critiques of the Maldivian government and led a campaign to find Mr. Abdulla, died after being repeatedly stabbed by assailants in his apartment building in Malé.

Before his murder, Mr. Rasheed, 29, had complained repeatedly to the police about receiving death threats. The authorities often failed to return his calls or dropped his complaints without investigating them, he said.

Over the course of a long inquiry into Mr. Abdulla’s disappearance, the authorities flip-flopped on whether they thought he had been abducted, and observers criticized the government for allowing a third suspect to leave the Maldives after the police released him from custody.

In an interview last year, Aminath Easa, Mr. Abdulla’s mother, angrily recalled attempts by the police to spray a pepper-based irritant into her eyes during an event marking 500 days since her son’s disappearance.

Ms. Easa said the investigation had never been transparent and that efforts to obtain information from the police were ignored.