Augusto Arnaut and his second in command, Mário Cerol, were both heard as formal suspects on Tuesday at a Leiria court.
The wildfires in question caused the death of at least 64 people, resulted in hundreds of injuries and destroyed and damaged hundreds of properties in the central Portuguese region.
This follows Constança Urbano de Sousa handing in her resignation as Home Minister in October due to successive deadly fires.
President Marcelo Rebelo de Sousa had already called for political accountability and even asked Parliament to ponder whether the current government deserved its confidence in the wake of the spate of wildfires.
The former minister, in her open resignation letter, revealed that she had offered to quit in June after the wildfires that claimed 64 lives, but was convinced to remain in office by Prime Minister António Costa.
She repeated her request after 44 people died in separate wildfires in October, which was then accepted.
Investigations into the June wildfire deaths, which all occurred in one night, found numerous shortcomings in the official response,
which all fell under her responsibility.
A failure in the communications system during the deadly June fire in Pedrógão Grande is believed to have contributed to the lack of coordination on the part of the firefighting and rescue services.
These are among the conclusions contained in the report ‘The complex of fires in Pedrógão Grande and surrounding municipalities’, which was submitted by Coimbra University’s Centre of Studies on Forest Fires to the government.
The report, drafted by Domingos Xavier Viegas, states that “the system of communications by radio and by telephone suffered a general failure in the whole region, both because of limitations inherent in the system, such as its lack of protection against exposure to fire, and because of being overloaded by users, and also because of deficient use of some of the systems”.
It added that this situation was “aggravated by the lack of availability of complementary means [of communication] due to the lack of planning.”
This failure, the report went on, “is believed to have contributed to the lack of coordination of the firefighting and rescue services, to the difficulty in requesting help on the part of residents, and to the worsening of the consequences of the fire.”
The report was commissioned by the government amid pressure from the political opposition in the wake of the June fires.
In related news, the Civil Protection Authority revealed this week it is to hire 50 aircraft to help tackle forest fires. The authority will also be purchasing four mobile units to boost its SIRESP emergency warning and safety network.
The aircraft will be operational throughout the whole of 2018 and 2019.
Among them are 38 helicopters to be used as an initial line of defence, one of which will go to Madeira.