Britain's record-breaking heat wave disrupted travel for a third day and firefighters remained on alert Wednesday even as cloudy skies and showers brought relief after two days of scorching temperatures.

Forecasters predict London will reach a high of 26 Celsius (79 Fahrenheit) on Wednesday, down from the record 40.3C (104.4F) set Tuesday at Coningsby in eastern England.

Environmental criminals in the Brazilian Amazon destroyed public forests equal the size of El Salvador over the past six years, yet the Federal Police — the Brazilian version of the FBI — carried out only seven operations aimed at this massive loss, according to a new study.

The destruction took place in state and federal forests that are "unallocated," meaning they do not have a designated use the way national parks and Indigenous territories do. According to official data, the Brazilian Amazon has about 580,000 square kilometers (224,000 square miles) of forests in this category, or an area almost the size of Ukraine.

Nearly 500 firefighters struggled to contain a large wildfire that threatened hillside suburbs outside Athens for a second day Wednesday, after hundreds of residents were evacuated overnight.

Fires continued to burn across southern Europe, but authorities in France, Spain and Portugal all reported improved conditions with a respite from severe heat wave conditions.

When José Antonio González started his afternoon shift sweeping the streets of Madrid, the temperature was 40 degrees Celsius (104 degrees Fahrenheit) amid a heat wave gripping Spain.

After a long time without a job, González couldn't afford to pass up a one-month summer contract to sweep the city, where he lived in a working-class neighborhood. Three hours later, the 60-year-old collapsed with heat stroke and was found lying in the street he was cleaning.

The 10-day heatwave that hit Spain left "more than 500 people" dead, Prime Minister Pedro Sanchez said on Wednesday.

Firefighters battling twin fires in southwest France said Wednesday the blazes were being brought under control thanks to improved weather conditions, but had not been stopped completely. 

A wildfire has burned at least five homes and resulted in about 300 homes being evacuated around a lake in north Texas amid sweltering temperatures and dry conditions, authorities said.

Officials are meeting in Kigali in Rwanda this week as part of the continent's first-ever Africa Protected Areas Congress in a bid to expand the preservation of land and marine wildlife, despite little funding and the low quality of many existing conservation areas in the region.

Just 14% of Africa's land and inland water ecosystems and 17% of coastal and marine areas are protected, according to United Nations estimates. The continent currently has 9,118 protected areas. Over 100 countries worldwide have ambitions to expand conservation efforts and protect wildlife from human-caused damages.

Millions of people in Britain woke from the country's warmest-ever night on Tuesday and braced for a day when temperatures are forecast to hit 40 degrees Celsius (104 degrees Fahrenheit), as a heat wave scorching Europe wallops a country more used to mild weather and rain.

The U.K.'s Met Office weather agency said provisional figures showed the temperature remained above 25 C (77 F) overnight in parts of the country for the first time.

A heat wave broiling Europe spilled northward Monday to Britain and fueled ferocious wildfires in Spain and France, which evacuated thousands of people and scrambled water-bombing planes and firefighters to battle flames in tinder-dry forests.

Two people were killed in the blazes in Spain that its prime minister linked to global warming, saying, "Climate change kills."