The perpetrator was Oussama Zariouh, a 36-year-old Moroccan national who lived in the Molenbeek municipality and who had assembled a defective explosive device.

[1] The Molenbeek municipality, where many of the perpetrators of the 2016 bombings lived, underwent a large-scale administrative check-up, with over 20,000 inhabitants being checked by law enforcement agencies.

[5][6][7] Testimonies of eyewitnesses and a photograph taken by a witness indicate a small incendiary device detonated, with limited explosive force, but with a loud "bang".

"[22][3] The attacker, identified as Oussama Zariouh (alt: Usamah Zaryuh)[23] was a 36-year-old Moroccan national who had moved from his home country to Belgium in 2002 and had been living in Molenbeek since 2013.

On the nearby Rue du Marché aux Herbes/Grasmarkt, another explosion could be heard as a result of a controlled detonation of a suspected vehicle by the Belgian bomb squad.

[21] The incident was used as an argument by advocates of stronger civil oversight within the Belgian political establishment to extend the mandate of soldiers patrolling the major cities in Belgium.

[21][38][clarification needed] The attack was understood by analysts at The Washington Post, The Wall Street Journal, and The New York Times as part of a shift in ISIS tactics as the group experienced an ongoing loss of territorial control in Syria and a concomitant loss in the capacity to train and dispatch operatives to commit attacks on foreign soil.

"[34] Writing in Behavioral Sciences of Terrorism and Political Aggression, Paige V. Pascarelli discussed this bombing as part of an exploration of the reasons why the Moroccan immigrant community in Belgium has produced a disproportionately large number of jihadists in contrast with the similarly poorly integrated and economically unsuccessful Turkish immigrant community.

[40] Thomas Renard of the EGMONT - The Royal Institute for International Relations in Brussels called Zariouh "the new face of jihad in Europe.