The incident occurred on Saturday at the Musee Juif de Belgique, located in the heart of the Belgian capital.
A man wearing a dark-colored jacket, baseball cap and sunglasses walked in the museum in broad daylight, pulled a Kalashnikov rifle out of a bag, and opened fire, killing three people.
A fourth person remains in critical condition.
Observers initially classified the shooting as an anti-Semitic attack. There is speculation, however, that the bloody assault may have been a targeted assassination that was part of a wider intelligence war between Israel, Iran, and Hezbollah.
Several counterterrorism experts, including Claude Moniquet, Co-Director of the European Strategic Intelligence and Security Center, have expressed the view that the shooter appeared to be a trained professional.
Referring to publicly available surveillance footage of the shooting, Moniquet said that the perpetrator of the attack, who remains at large, behaved as “an unemotional murderer, someone who had already witnessed death and perhaps killed before”.
Moniquet’s comments came shortly after an article by Amir Oren, military affairs correspondent for Israeli daily Ha’aretz, in which he suggested that the attack may have been an act of retaliation by Iranian or Hezbollah operatives, who have been engaged in a lengthy tit-for-tat war with Israeli intelligence since at least 2009.
Oren noted that two of the victims of the attack, Emmanuel and Mira Riva , were civil service accountants who had spent years in government service.
The couple, who were in their 50s, had previously served at Israel’s embassy in Berlin, Germany, while Mira was a member of staff at the Office of the Prime Minister of Israel, which, as British newspaper The Guardian notes, “is often a euphemism for the Mossad and Shin Bet secret services”.
Oren’s article, which is the main source of the speculation about the attack, reads somewhat abstract and hypothetical. But some have suggested that the veteran military affairs analyst appears to be trying to hint at an important clue while being mindful of strict Israeli military censorship rules, which apply to nearly all intelligence-related news stories in the country.