French police have charged three men with “attempted murder in an organised group in connection with a terrorist enterprise” after they found several gas canisters placed in an apartment block in Paris.  It’s not clear why the canisters were not detonated or why an apartment complex was targeted.

The Times of Israel reports:

Three men have been handed preliminary terror-linked charges in the failed attack at a residential building in an upscale Paris neighborhood with gas canisters that failed to ignite.

The three, identified as Amine A, his cousin Sami B, and Aymen B., were charged late Friday with “attempted murder in an organized group in connection with a terrorist enterprise” and placed in pre-trial detention, a judicial source said.

All three were arrested on Monday evening, two days after the device was found in a block in the 16th arrondissement, one of the city’s most exclusive neighborhoods.

In total, police found four gas cylinders — two of them in the hallway attached to a mobile phone which investigators believe was meant to be used as a detonator. The other two were on the pavement outside.

The judicial official said on Saturday that the three were placed under formal investigation late Friday in the mysterious attack attempt. The official wasn’t authorized to speak on the record in an ongoing investigation.

Two of the alleged terrorists are on a terror watch list and known to have been radicalized by French authorities.

The shift from public venues to apartment residences has French officials puzzled.

The Times of Israel continues:

Anti-terrorism prosecutor Francois Molins said at a Friday news conference that investigators have yet to find a “logical explanation” for why the building was targeted.

Two of three men, Aymen B. and Amine A., are among thousands on a list for radicalization.

Three of their associates who were taken for questioning earlier this week have all been released.

“The consequences in terms of human life and material damage could have been dramatic,” Molins said on Friday, adding that it was unclear why they chose to target that particular building in Porte d’Auteuil.

It also remains unclear why the men did not activate the device. Police tracked them down by means of DNA found at the scene.