Social activists in Dhaka, Bangladesh’s capital, protest against the killing of an American blogger of Bangladeshi origin, Avijit Roy, who was hacked to death on Feb. 26, 2015. (Munir Uz Zaman/AFP via Getty Images)

Police in Bangladesh said Monday that they are investigating whether a small terrorist group suspected in the hacking death of an American blogger has links to al-Qaeda after a video surfaced over the weekend of an al-Qaeda leader asserting responsibility for the attack.

Asim Umar, the purported leader of al-Qaeda in the Indian Subcontinent (AQIS), posted a video on a jihadist forum claiming responsibility for the deaths of Avijit Roy, a secularist blogger killed in Bangladesh’s capital, Dhaka, in February, and other “blasphemers” from Bangladesh and Pakistan.

“These assassinations are part of a series of operations initiated on the orders of our respected leader,” Umar reportedly said in the video, referring to al-Qaeda’s Ayman al-Zawahiri. The video was translated and analyzed by the Bethesda, Md.-based Site Intelligence Group.

Analysts in Pakistan and India, as well as some law enforcement officials in Bangladesh, expressed skepticism, theorizing that the claim could be a ploy to gain influence for AQIS, al-Qaeda’s South Asia wing. Zawahiri established the branch in September to counter the rise of other terrorist groups such as the Islamic State and to boost al-Qaeda’s waning influence in South Asia.

Lt. Col. Abdul Kalam Azad, director of intelligence for Bangladesh’s Rapid Action Battalion, said investigators were analyzing the video to determine its authenticity.

“Maybe they are taking a chance to increase [their] popularity,” Azad said. “But, obviously, the video is a new point for us, and we also are taking it very seriously.”

Police in Bangladesh said they suspect that a local group called Ansarullah Bangla Team (ABT), with about 100 or so “well-educated” active members, was behind Roy’s death.

Police said Roy, a resident of suburban Atlanta who was killed by machete-wielding assailants on Feb. 26 as he was leaving a Dhaka book fair with his wife, was targeted for secularist views he had espoused on a blog and in a book called “The Virus of Faith.” One suspect has been arrested.

After Roy’s death, another blogger from Bangladesh also was hacked to death; two others were attacked by extremists in 2013, and one died.

“So far, our investigation reveals that some members of ABT, they are perpetrators in [the Roy] incident, and we are trying to trace them and apprehend them,” said Monirul Islam, joint commissioner of the detective branch of the Dhaka Metropolitan Police. “We know ABT is the closest relative of al-Qaeda, as they follow their ideology, strategy, tactics, everything.”

Al-Qaeda has had enduring links with Bangladesh, a Muslim-majority country that split from Pakistan in 1971. According to terrorism expert Ajai Sahni, the network’s influence there dates to 1992, when the terrorist group Harkat-ul-Jihad-al-Islami Bangladesh was set up with direct funding from al-Qaeda leader Osama bin Laden.

“It is probable that extremist elements in Bangladesh have maintained contacts with al-Qaeda and now with AQIS,” said Sahni, executive director of the Institute for Conflict Management in New Delhi. But, he cautioned, “local groups like ABT would essentially receive ideological direction, rather than operational dictates or target selection, from al-Qaeda and AQIS.”

In recent weeks, AQIS’s leadership has been decimated by drone attacks, including one in January that killed two Western hostages, experts say. Pakistani officials told The Washington Post in April that a key AQIS leader, an American raised in Pakistan, also was killed in that attack.

“My sense is that AQIS at this point is more aspirational than operational,” said Michael Kugelman, senior associate for South and Southeast Asia at the Woodrow Wilson International Center for Scholars. “It is a formal group with a leadership hierarchy, but it has little to show for in what it has done on the ground.”

AQIS had launched only one high-profile operation — an abortive attempt to take over a Pakistani navy frigate in September. The operation was foiled after an intense firefight between security forces and militants in which several terrorists died.

David Bergman in Dhaka and Shaiq Hussain in Islamabad, Pakistan, contributed to this report.

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