Siddique ul-Islam, later known by the alias Bangla Bhai, was born in 1970 in Kannipara village, Gabtoli upazila, Bogra, Bangladesh. The son of Nazir Hossain Pramanik, Siddique grew up in a conservative environment. Details about his early education are murky, with Siddique claiming to have received a master’s degree in Bangla from Rajshahi University in 1995. However, university records did not confirm this. He later clarified that he studied at Azizul Haq University College, affiliated with Rajshahi University.

He was a teacher of Bangla in Dhaka-based coaching centers, which reportedly earned him the affectionate nickname "Bangla Bhai" from students. However, these coaching centers were never named publicly, and some suspected the narrative was crafted for legitimacy. Siddique was politically active in his youth, he claimed early support for Bangladesh Chhatra League, and later joined Islami Chhatra Shibir, the student wing of Jamaat-e-Islami. He claimed to have left the group in protest of their tolerance for female leadership, which he viewed as incompatible with Islamic values.

By the early 2000s, Siddique had joined Jagrata Muslim Janata Bangladesh (JMJB) — a militant offshoot with ideological links to Al-Qaeda. He quickly rose through the ranks, eventually becoming its military commander and a key member of its Majlis-e-Shura (decision-making board).

Bangla Bhai’s reign of terror began in 2004, when JMJB began operating in the Rajshahi region of northwestern Bangladesh. The group first posed as vigilantes, claiming to crack down on local criminals, but soon escalated into full-blown jihadist activity, with torture, public executions, and bombings becoming part of their tactics. Human rights group Taskforce against Torture documented over 500 cases of abuse committed by Bangla Bhai’s forces.

With support from corrupt police and local officials, Bangla Bhai established a network of militant training camps hidden in madrasas and forest areas. The operation was heavily funded by foreign donations—ostensibly for mosque construction—redirected for terrorism.

The most shocking event occurred on 17 August 2005, when 500 small bombs detonated simultaneously in 63 out of Bangladesh’s 64 districts within one hour. Although the death toll was relatively low (3 killed, ~100 injured), the message was clear: JMJB had operational reach across the nation.

The violence escalated:

• 14 November 2005 – Two judges in Jhalakathi were murdered via bomb thrown into their car.
• 29 November 2005 – In Gazipur, the country’s first-ever suicide bombing killed 7 people, including the bomber. In Chittagong, a separate suicide bombing killed 2 police officers and injured 13 more.

By this time, both JMJB and the Jamaat-ul-Mujahideen Bangladesh (JMB) had claimed joint responsibility for the attacks. Bangla Bhai and his co-leader Shaykh Abdur Rahman were declared fugitives.

On 6 March 2006, after a months-long manhunt, Rapid Action Battalion (RAB) forces located and arrested Bangla Bhai’s wife and child in Mymensingh. Acting on intel provided by his wife, RAB surrounded a tin-roofed hideout in Rampur village, Muktagachha.

As a RAB officer peeked inside, Bangla Bhai shot him in the head, then detonated a bomb inside the room. The blast injured both himself and his bodyguard, destroyed the house, and started a fire. RAB surrounded the building and called for surrender. At 7:30 a.m., Bangla Bhai emerged injured and surrendered.

Crowds from nearby villages gathered to witness his capture. As he was transported to the hospital, locals cheered and applauded, hailing RAB officers as heroes.

Bangla Bhai was tried and convicted for the 2005 assassination of two judges in Jhalakathi. He received a death sentence, along with five other senior JMB militants.

On 30 March 2007, Siddique ul-Islam, alias Bangla Bhai, was executed by hanging, closing a dark chapter in Bangladesh’s struggle with homegrown extremism. The execution was seen as a major victory for the state.

In 2010, his wife Fahima (alias Farzana) was convicted and sentenced to 20 years in prison for possessing explosives, alongside two other JMB operatives.