This contradict earlier reports that a Canadair aircraft went down near the central PedrÃ³gÃ£o Grande area.
More than 1,000 firefighters on the ground and planes from several countries are battling the fires.
The fires have claimed the lives of at least 64 people and since Saturday.
Many of the victims died in their cars as they tried to escape.
More than 130 people have been injured.
Portugal fires: Varzeas mourns villagers who fled
Civil protection officials have said they expect the blazes to be under control soon, but warn that soaring temperatures are hampering efforts.
The week's highest temperatures in the area are expected to reach about 38C (100F) and, together with windy conditions, could reignite fires that have already been brought under control.
Wildfires are an annual menace in Portugal. More broke out there between 1993 and 2013 than in Spain, France, Italy or Greece, the European Environment Agency reported last year, despite the country's relatively small geographical size.
Given that, was this year's tragedy preventable? Could Portugal have done anything more to save lives and minimise the damage?
Read more: Just what makes Portugal such a tinderbox?
One of the worst-hit areas was around the village of Nodeirinho. Thirty bodies were found inside cars and another 17 next to vehicles on the N-236 road.
Portuguese media have dubbed the N-236 the "road of death".
Portuguese Prime Minister Antonio Costa has questioned why the emergency services did not close the road.

It comes after similar concerns about pressure on bed availability at the Borders General.
NHS Dumfries and Galloway said an upsurge in demand for services was being seen across Scotland.
It said work was ongoing to improve "patient flow" to deal with the increase in hospital admissions.
Infection control manager Elaine Ross said flu and other respiratory viruses were circulating in communities across the region.
She urged everyone to play their part in tackling the issue.
"Currently, the demand on our local hospital is extreme," she said.
"Patients are arriving at our emergency department and via GP referrals with flu-like symptoms and persistent coughs that may be compounded by underlying conditions.
"The flu vaccine is effective but won't protect against other viruses that are going round."
She asked anyone with symptoms to take lots of fluid and paracetamol and to stay indoors and rest until they felt better.
"We are also urging people to not visit relatives in the hospital if they are showing any symptoms," she said.
"It is vital that we stop the spread of infection."
Interim general manager Gail Meier said staff were "working round the clock" to assess patients and determine the need for admissions.
She said they aimed to ensure that people were "seen, treated and either discharged or admitted in a timely manner".
"It is a very demanding time for the health service and I take the opportunity to urge everyone to consider the use of emergency services as it is a finite resource," she said.
"Community pharmacies and NHS 24 offer help and advice as an alternative to attending hospital.
"I would like to thank everyone for their commitment over the past few weeks and 365 days of the year for that matter. It does not go unnoticed."

Agents arrested more than 150 people on sex-trafficking charges in dozens of cities including Atlanta, Denver and Seattle.
The youngest victim found was 12 years old, the FBI said.
The FBI targeted hotels, casinos and lorry stops to find underage victims.
The majority of the teens found were girls. Agents also found three boys and three transgender teens.
The FBI worked with local police departments and the National Center for Missing and Exploited Children to help the teenage victims to find shelter and get medical attention.
The agencies want to ensure the teenagers do not return to prostitution.
"When kids are treated as a commodity in seedy hotels and on dark roadsides, we must rescue them from their nightmare and severely punish those responsible for that horror," FBI Director James Comey said in a statement.
The raids involved about 500 local police departments from across the country. A similar FBI-led campaign carried out last year uncovered about 160 teenagers working as prostitutes.
Reports that a firefighting plane crashed during an operation to tackle huge blazes in central Portugal have been denied by the country's civil protection authority.
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Health chiefs have warned Dumfries Infirmary is facing "extreme" demand from people with flu-like symptoms and persistent coughs.
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The FBI has broken up several sex trafficking rings across the US, uncovering more than 100 sexually exploited teenagers in a nationwide operation.