The GNR Has Detained 173 Fire Suspects This Year, the Most in a Decade, Out of 6,200 Fires It Investigated

The GNR (Guarda Nacional Republicana, the national gendarmerie) has detained 173 people this year on suspicion of the crime of forest fire, and investigated 6,200 fires. The detention figure is the highest in a decade, and the officer who gave it said so plainly.

"Of the last 10 years, it is clearly the year with the highest number of detentions," said Colonel Ricardo Alves, director of the SEPNA (Serviço de Proteção da Natureza e do Ambiente, the GNR's Nature and Environment Protection Service). "Which also tells us there is still work to be done in this area."

Alves was speaking on Friday in Vila Pouca de Aguiar, at a set of criminal investigation sessions run by the GNR's Vila Real command to mark the territorial command's 17th anniversary. The two subjects chosen for the sessions were forest fires and domestic violence, the two most-reported crimes in that Trás-os-Montes district. The 173 figure runs from the start of the year to Friday, and covers the whole country.

Six thousand two hundred investigations, and what they found

The investigation count is the larger number and the less discussed one. The GNR has looked into 6,200 fires so far this year, which Alves described as broadly in line with last year.

What those investigations turn up is not mostly arson in the sense the word conjures. Burning of agricultural and forest residues, the practice known in Portuguese as queimas and queimadas, accounts for what Alves called a large slice of all the causes established to date. Deliberate ignition comes second, which he broke into fires set by people who can be held criminally responsible and fires set by people who cannot.

That ordering is the practical heart of it. The largest single identified cause of fire in Portugal is not malice. It is a legal, traditional and widely practised form of land management that goes wrong, and which the law regulates rather than forbids outright.

The profile, and the part of it that is changing

Alves also set out what the GNR thinks it knows about who starts fires. Most suspects are men in their fifties. But he flagged a rise in women among those detained: "Of the total detained, 19 percent are female, the rest are male, who continue to be the great majority."

Nineteen percent is a figure worth holding lightly. It is a share of detentions rather than of fires, and detentions are a product of how and where a police force looks as much as of who offends. Alves framed the profiling as an operational tool rather than a sociological finding: "Knowing the gender of suspects, the age bracket, the motivations, we can anticipate the locations too and anticipate the possible perpetrators, and so we cannot separate the two," he said, meaning prevention and investigation.

He also warned that the season is not over. Weather conditions at this point in September, he said, mean more fire occurrences are still possible.

Why a record detention count is not a record fire year

It would be easy to read 173 detentions as evidence of a worse fire year. The area burnt says otherwise. Portugal's burnt area is down roughly three quarters on the year, and a fire specialist quoted on that figure earlier this month credited the weather rather than any change in government policy.

Both things can be true at once. A decade-high detention count in a year of sharply reduced burnt area points at enforcement effort and investigative capacity, not at a surge in offending. The GNR investigated a similar number of fires to last year and detained more people out of that similar number. That is a change in outcome per investigation, which is what a police force can actually move.

The context around it has been busy. Parliament approved a criminal policy law for 2026 to 2028 in June that named forest fire as a priority and put prison work crews into forest clearing. The prison service opened an arsonist rehabilitation programme across seven prisons in July. And the annual crime report in April had already logged arson among the rising categories for 2025.

What this means for foreign residents

• Burning garden and land waste is regulated, not free: queimas and queimadas are the single largest identified cause of the fires the GNR investigates. If you own rural land in Portugal, the rules on when and how you may burn, and when you must instead register or seek authorisation, are the rules most likely to put you on the wrong side of a fire investigation.
• A fire on your land is investigated, whoever started it: 6,200 investigations against a far smaller number of detentions means most enquiries end without an arrest. Being asked questions by SEPNA after a fire near your property is routine.
• The season has not closed: the SEPNA director expects further occurrences given current weather. Nine districts went under a yellow heat warning for Saturday morning. Land-clearing obligations and local burning bans still apply.
• SEPNA is the unit to know: environmental and forest offences in Portugal sit with this GNR branch rather than with the PSP or the Polícia Judiciária. It is also the body you report an environmental offence to.
• Detentions are not convictions: the 173 figure counts people detained on suspicion. Portuguese criminal procedure takes cases through investigation and trial from there, and the outcome data for this year does not exist yet.

The number that will settle whether 2026 was a turning point is not 173. It is how many of those detentions become charges, and how many charges become convictions, neither of which the GNR publishes and both of which arrive years later. What Friday's figure does show is a force investigating roughly the same volume of fires as last year and getting a materially different result out of it, in a summer when far less of Portugal burned.