He is being held in pre-trial detention while the investigation by the Judiciary Police continues.

In a statement, the Santarém District Attorney's Office said that the coercion measure was applied on Tuesday afternoon, after the detainee’s first interrogation given the "dangers of continuation of criminal activity and alteration of public order and tranquility".

The attorney general's office also mentioned a history of alcoholism, "not resolved even after rehab treatments and behavioral disorders that had contributed to his retirement due to incapacity for the public police service".

The man is suspected of having started the fire that occurred at the beginning of Friday night near the area where he lives with his father.