DHAKA: Bangladesh Prime Minister Sheikh Hasina Sunday dismissed the self-styled Islamic State's (IS) claim to have killed two foreigners, saying police still had no evidence to confirm the group was behind the murders.

Her remarks came a day after 66-year-old Japanese citizen Hoshi Kunio was shot dead in northern Bangladesh, the second foreigner to be murdered in the South Asian nation in less than a week.

A 50-year-old Italian, Cesare Tavella, was shot dead last week near Dhaka's diplomatic zone in another attack also claimed by IS.

"We have still not found any involvement (of IS). We have to investigate," Hasina told reporters.

"We've got no clues. If someone claims responsibility, why should we have to accept it?" she added.

"Until we find out the link through investigation, I don't think there is any reason for us to accept it."

Italian aid worker Tavella was shot three times on September 28 by attackers who fled on a motorcycle ─ an attack the Bangladesh government described as an "isolated incident" in an attempt to calm security fears.

Kunio was riding in a rickshaw when he was shot dead by three unidentified attackers riding a motorbike in the town of Kaunia in Rangpur district.

Home Minister Asaduzzaman Khan Kamal has rejected any IS presence in the country but said the two killings appeared to be linked.

"I can again say boldly that there is no existence of IS in Bangladesh," he said on Sunday, adding such murders were "an attempt to create instability in the country".

Bangladesh prides itself on being a mainly moderate Muslim country. But the gruesome killings of a series of atheist bloggers this year have rocked the nation and sparked a crackdown on local hardline Islamist groups.

After the murder of the Italian, international schools closed temporarily and Western embassies restricted their diplomats' movements, while Australia's cricket team cancelled a planned tour due to security concerns.

Also read: Militant group IS says it gunned down Italian in Bangladesh