The Islamist extremists who murdered 20 hostages they had taken at a restaurant in the Bangladeshi capital of Dhaka were members of a local terrorist organisation, not Islamic State (Isis) militants, according to a senior government official. Despite this, Isis (Daesh) has still attempted to claim responsibility for the 11-hour siege which ended in tragedy on Saturday.

Asaduzzaman Khan, Bangladesh's home minister, has told the media that the hostage-takers were representatives of Jama'atul Mujahideen Bangladesh (JMB), a local Islamist terror group, which is not connected to IS, and has been banned for more than a decade.

Twenty-two people were killed in total after gunmen seized the Holey Artisan Bakery, including three locals, seven Japanese aid workers, an Indian student and nine Italian businessmen and women. Two police officers were killed, with another 30 injured, after at least seven armed men stormed the cafe on Friday. Bangladeshi commandos stormed the premises, killing six of the men and rescuing 13 hostages.

The seventh man is currently being interrogated by intelligence officers, while the authorities have released the names of his six dead colleagues. Khan told the AFP that the attackers were well educated, and came from wealthy families.

"They are all highly educated young men and went to university. No one is from a madrassa," he said, suggesting that militancy "has become a fashion". He also echoed his government in denying that IS or al-Qaeda were operating in the country, insisting that home-grown terror groups have been responsible for the uptick in killings that have swept the country in the past two years.

JMB has long been notorious in the country. In 2005 it set off more than 500 bombs in 64 districts at the same time.

For its part, IS has released a statement claiming to be behind the attack, and warning "crusader countries" that their citizens would be at risk "as long as their aircraft are killing Muslims".

Dhaka restaurant shooting
An injured man receieves help after an attack at a restaurant in DhakaAFP/Getty