The suspects were arrested on charges relating to firearms, narcotics and other offences, police said on Sunday.

A total of 5,324 people have been detained since the crackdown started on Thursday across Bangladesh, according to the officials. At least 85 of them are believed to be Islamic militants.

Police launched the raids in response to a spike in brutal, religiously charged attacks that saw the wife of a senior counterterrorism official stabbed and shot dead. The crackdown is expected to last at least one week.

"We will have to prevent the emergence of militancy collectively, as a whole nation," national police chief Shahidul Hoque said.

Government disputes IS links

Islamist militants have killed over 30 people in Bangladesh since early last year, including atheist bloggers, gay rights activists, university professors, Hindus, and Christians.

Most of the attacks in the Muslim nation were claimed by the "Islamic State," with al Qaeda also claiming several of them, monitor groups say. However, the Dhaka government has pointed the finger at domestic jihadists instead, insisting that international terror groups have no presence in Bangladesh.

Police said that two home-grown groups, Jumataul Mujahedeen and Ansarullah Bangla Team, were attempting to force sharia law on the nation of 160 million people.

On Saturday, Prime Minister Sheikh Hasina vowed to catch "each and every killer" responsible for the violence. Hasina also implied that her political opponents were linked with the groups and the bloody campaign.

The Bangladeshi opposition denied the charges, saying that many of those arrested in the crackdown were "ordinary and innocent people."