Two years have elapsed since LGBT magazine editor Xulhaz Mannan and his friend were murdered, but police could not yet arrest any of the four killers, let alone conclude the probe.

USAID staff Xulhaz, who used to work as a protocol officer of former US ambassador Dan W Mozena, and his friend Khandoker Mahbub Rabby Tonoy were hacked to death inside Xulhaz' flat in the capital's Kalabagan area on April 25 last year.

Five killers, aged between 25 and 28, were seen running away in footage of a CCTV camera installed about 300 yards from the house.

Four of the five youths entered the flat on the first-floor posing as couriers and directly took part in the killings, police said.

“We have identified the killers and drive is on to arrest them,” Saiful Islam, additional deputy commissioner of Counter Terrorism and Transnational Crime (CTTC) unit of Dhaka Metropolitan Police, which is now investigating the case, told The Daily Star yesterday.

Investigators also claimed that they had already arrested four persons -- Shariful Islam Shihab, Rashidun Nabi, Arafat Rahman Sazzad alias Siam, and Mozammel Hossain alias Saimon -- who aided and abetted the killings.

Shariful, arrested in Kushtia on May 14, 2016, supplied firearms to the attackers and Rashidun Nabi, also an accused in Jagannath University student Nazim Uddin Samad murder case, trained the killers, claimed police.

As none of the four killers are arrested yet, the investigators said they are not sure when they would be able to submit the charge sheet.

Meanwhile, expressing frustration over the state of probe, Xulhaz's elder brother Minhaz Mannan Emon said, “It's nothing, but a farce.”

Apparently, police have no interest in arresting the killers, he alleged. “We have no more expectation,” he told The Daily Star.

A day after the killings, Ansar Al Islam, the so-called Bangladesh chapter of al-Qaeda in Indian Subcontinent (AQIS), claimed responsibility for the double murder.

The US State Department, the US embassy in Dhaka,

 Amnesty International and other national and international organisations strongly condemned the killings.