The Islamic State jihadist group has claimed responsibility for the killing of an Italian aid worker in Bangladesh, the SITE Intelligence group said.

"A security detachment has tracked Mr. Tavella through the streets of Dhaka and then killed him using silenced weapons," the jihadist group said in an online statement, according to New York Times.

1) #ISIS claim of killing Italian AISD employee Tevella Cesare shows that ISIS-AQ competition has reached #Bangladesh pic.twitter.com/zLEji4fxd5

— Rita Katz (@Rita_Katz) September 28, 2015

"ISIS claim of killing Italian AISD employee Tevella Cesare shows that ISIS-AQ competition has reached Bangladesh," Rita Katz, director of SITE Intelligence group, tweeted.

Italian national Cesare Tavella, 50, was gunned down by an unidentified attacker in Dhaka's high security diplomatic zone on Monday evening. Tavella was a technical director with Profitable Opportunities for Food Security (Proofs), a project of Netherlands-based organization ICCO Cooperation.

"One bullet hit his left hand. It was a through-and-through gunshot. He was also shot twice in his back. One of those bullets pierced through his chest. He was shot from a close range. It appears that these bullets were fired from a revolver," said forensic expert Abu Shama, who conducted the autopsy, according to bdnews24.

Bangladeshi authorities, however, said that the involvement of the Islamic State group in the killing of the Italian man is yet to be confirmed.

"We are looking into everything which that might have been the motive behind the murder," home minister Asaduzzaman Khan Kamal said Tuesday, according to Daily Star.

Western countries, including the United States, alerted their citizens in Bangladesh, reported The Hindu. U.S. advised its nationals to limit their movements in the country.