ISIS claimed responsibility for killing Cesare Tavella last month
, but the city's Police Commissioner, Muntashirul Islam, said Monday that none of the arrested men were believed to have any ties to the Islamic militant group.
The motive he outlined for the attack on Tavella, who was gunned down as he was jogging home from a swimming pool, is nonetheless disturbing for overseas citizens living in Bangladesh.
Islam described the four suspects, all Bangladeshi citizens, as contract killers who were hired by a person they refer to as "Big Brother" to kill a foreigner, preferably with "white skin."
Police are still hunting for "Big Brother," who they say they don't believe is connected to ISIS either.
Police: No link to killing of Japanese man
The assailants shot Tavella, 51, in Gulshan, the diplomatic zone of Dhaka, on the evening of September 28. They fled on a waiting motorbike, taking nothing from the victim.
Three of the arrested men were directly involved in the killing and the other was responsible for renting the motorbike used in the attack, according to Islam.
The four suspects, aged between 30 and 40, have confessed to involvement in the attack, he said, adding that the investigation is ongoing.
The statements from police leave a lot questions about the killing and ISIS' claim of responsibility.
The militant group also said it was behind the killing of a Japanese man in northern Bangladesh in early October
. Islam said police had so far found no connection between the two attacks.
ISIS claims responsibility for bombing
According to the terrorist monitoring group SITE, ISIS
also claimed responsibility for the bombing of a gathering of Shiite Muslims in Dhaka on Saturday. That attack killed a teenage boy and wounded more than 50 other people, according to police.
ISIS, which espouses an extreme version of Sunni Islam, has targeted Shiites in Syria and Iraq, where it controls territory, and elsewhere. Shiites are a minority group in Bangladesh, most of whose citizens are Sunni Muslims.
The killings of the Italian and Japanese citizens had prompted warnings from several foreign governments to their citizens working or traveling in Bangladesh.
The police commissioner said Monday that security had been stepped around the capital since the attack on the Italian, including the deployment of more officers and the installation of more security cameras.