Bangladesh police on Sunday arrested four female members of a home-grown militant group blamed for the bloody attack on a cafe earlier this month in which 22 people were killed, most of them foreigners.
Authorities ramped up the hunt for militants across the country after five young men stormed an upmarket restaurant popular with foreigners in the nation's capital and took hostages. Among those killed were nine Italians, seven Japanese, an American, and an Indian.
The five militants were killed when security forces moved in. The attack was reportedly one of the worst terrorist attacks on Bangladesh soil.
Police believe that Jamaat-ul-Mujahideen Bangladesh (JMB), a banned group that has pledged allegiance to the Islamic State, played a significant role in organizing the group of wealthy university students who carried out the attack.
The four female members of the group, aged 18 to 30, who were arrested in the northwestern district of Sirajganj, are believed to have been plotting another attack, police said.
"Acting on a tip-off, our force raided a rented house where a large amount of grenade-making materials, crude bombs and jihadi books were also found," district police superintendent Siraj Uddin Ahmed told reporters.
Investigators were trying to determine if the women had any link to the Dhaka cafe attack.
Earlier this week, on Thursday, four other members of the banned group — including a regional head — were arrested.
Al-Qaeda and IS have made competing claims for a series of killings of liberals and members of religious minorities in the country over the past year.
The government dismissed the claims and instead blamed domestic militant groups, but security experts say the scale and sophistication of the cafe assault suggested links to a trans-national network.
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