The computer engineer reportedly ran the social media operations for the militant group behind the attack. Photograph: (AFP)
Ashfak-e-Azam is the information technology chief of the Sarwar-Tamim group, a new faction of the JMB blamed for the Dhaka cafe seige
Bangladeshi security forces Wednesday arrested a computer engineer said to run the social media operations for a group accused of mounting a deadly attack on a Dhaka cafe.
Ashfak-e-Azam and three other suspects were detained in a raid in the capital in which guns, explosives and ammunition were also seized, officials said.
"Azam is the information technology chief of the Sarwar-Tamim group," said Mufti Mahmud Khan, a spokesman for the elite Rapid Action Battalion which carried out the raid.
Sarwar-Tamim is a new faction of Jamayetul Mujahideen Bangladesh (JMB), the Islamist outfit blamed for a string of deadly attacks including a siege at an upscale Dhaka cafe last July in which 22 people -- mostly foreigners -- were killed.
Azam, 25, had been involved with the group since 2011, running its website and social media accounts, a senior official at the anti-terrorism battalion said.
Police say the four men arrested in Wednesday's raids were trained militants.
Bangladesh, a Muslim-majority country of 160 million, has been reeling from a wave of attacks by extremists on foreigners, rights activists and religious minorities.
Many of these assaults have been claimed by the Islamic State group or the regional branch of al-Qaeda.
But Prime Minister Sheikh Hasina's secular government has pinned the blame on local extremists, especially JMB, rejecting suggestions global jihad outfits had any foothold in the country.
Since the cafe attack security forces have cracked down on extremist groups, killing around 50 suspected militants including the founders of the new JMB faction.