Bangladeshi police Saturday said they have arrested an Islamist extremist accused of being one of the "masterminds" of last year's deadly siege at a Dhaka cafe where 22 hostages were killed.
A police spokesman said Jahangir Alam was detained Friday night by counter-terrorism forces in Elenga, a town some 120 kilometres (63 miles) north of the capital.
"He is one of the main masterminds of the Holey Artisan Bakery (cafe) attack," Yusuf Ali, an additional deputy commissioner of the Dhaka police force, told AFP.
"He was a member of a new faction of Jamayetul Mujahideen Bangladesh (JMB) and was directly involved in the murder of at least 22 religious minorities including Hindu priests and a Christian and foreigners (at the cafe)," he said.
Japanese and Italian diners were among the 18 foreigners shot and hacked to death in the attack on July 1 last year.
The siege lasted for 10 hours until army commandos, using armoured vehicles, stormed the compound.
Sanwar Hossain, an additional deputy commissioner of the police's counter-terrorism and transnational crime unit, said Alam was a close associate of Tamim Chowdhury, the slain Bangladeshi Canadian, who was named as the primary architect of the cafe siege.
"(Alam) was notorious. He led around two dozen attacks on religious minorities outside the capital," he told AFP.
Alam, 32, was present with Chowdhury at a Dhaka hideout where they planned and organised the cafe attack, Hossain added.
The arrest comes a week after police killed two Islamist extremists including another plotter of the cafe siege in a shootout in Dhaka. Chowdhury was killed during a raid outside the capital in August last year.
The country's security forces launched a deadly crackdown against Islamist extremists following the attack, which badly undermined Bangladesh's reputation as a relatively moderate Muslim nation.
Since the siege, security forces have killed around 50 Islamist extremists, including most of the alleged leaders of Jamayetul Mujahideen Bangladesh.
However, the Islamic State (IS) organisation also claimed responsibility for the cafe attack, posting images of the carnage as it happened and photos of the gunmen who had posed with the group's black flag.
Bangladesh is reeling from a wave of attacks on foreigners, rights activists and members of religious minorities.
While many of those attacks have been claimed by IS or Al Qaeda, Prime Minister Sheikh Hasina's secular government has blamed local militants, denying that international jihadists have gained a foothold in Bangladesh.