Forest fires across central Portugal have killed at least 62 people and injured 59 others including five in a serious condition, reports AFP citing officials.

Several firefighters are among the injured, and six of them are seriously wounded, Portugal's public broadcaster RTP has reported. Two have been reported missing.

Portugal on Sunday declared three days of national mourning.

Firefighters work to put out a forest fire near Bouca, in central Portugal, June 18, 2017. /VCG Photo

Nearly 1,700 firefighters tackled 156 locations of fire. Many of those that died were found inside their cars or just next to their vehicles on a small section of road leading to a motorway. This has become one of the most fatal forest fires in recent memory. 

The forest fire near Bouca in central Portugal, June 18, 2017. /VCG Photo‍

Portuguese President Marcelo Rebelo de Sousa visited the site and said the "situation is unfortunately atypical." He also added "it was not possible to do more than what has been done" in terms of prevention and immediate response efforts.

"I don't want to talk yet about the cause of the fire because we are facing the greatest tragedy of human lives so, what we must do now is to calmly provide all the resources to fight the fires,” said Antonio Costa, the Portuguese prime minister

The deadly blaze occurred in Pedrogao Grande, a mountainous area 200 kilometers southeast of Lisbon. 

Portugal was sweltering under a severe heatwave on Saturday, with temperatures exceeding 40 degrees Celsius in several regions.