MANILA, Philippines (AP) — Typhoon Noru blew out of the northern Philippines on Monday, leaving five rescuers dead, causing floods and power outages and forcing officials to suspend classes and government work in the capital and outlying provinces.

The most powerful typhoon to hit the country this year slammed into the coast in Burdeos town in Quezon province before nightfall on Sunday then weakened as it barreled overnight across the main Luzon region, where thousands of people were moved to emergency shelters, some forcibly, officials said.

Gov. Daniel Fernando of Bulacan province, north of Manila, said five rescuers, who were using a boat to help residents trapped in floodwaters, were hit by a collapsed wall then apparently drowned in the rampaging waters.

“They were living heroes who were helping save the lives of our countrymen amid this calamity,” Fernando told DZMM radio network. “This is really very sad.”

On Polillo island in northeastern Quezon province, a man was injured after falling off the roof of his house, officials said.

More than 17,000 people were moved to emergency shelters from high-risk communities prone to tidal surges, flooding and landslides in Quezon alone, officials said.

More than 3,000 people were evacuated to safety in Metropolitan Manila, which was lashed by fierce wind and rain overnight. Classes and government work were suspended Monday in the capital and outlying provinces as a precaution although the morning skies were sunny.

The entire northern provinces of Aurora and Nueva Ecija, which were hit by the typhoon, remained without power Monday and repair crews were at work to bring back electricity, Energy Secretary Raphael Lotilla told President Ferdinand Marcos Jr. in a televised meeting he called to assess damages and coordinate disaster-response.

Marcos Jr. praised officials for evacuating thousands of people to safety as a precaution before the typhoon hit which prevented large number of casualties despite the Noru’s potentially disastrous force.

Noru underwent an “explosive intensification” over the open Pacific Ocean before it hit the Philippines, Vicente Malano, who heads the country’s weather agency, told The Associated Press on Sunday.

From sustained winds of 85 kilometres per hour (53 mph) on Saturday, Noru was a super typhoon just 24 hours later with sustained winds of 195 kilometres (121 miles per hour) and gusts of up to 240 kph (149 mph) at its peak late Sunday.

By Monday morning, Noru had sustained winds of 140 kph (87 mph) and gusts of 170 kph (105 mph) and was moving westward in the South China Sea at 30 kph (19 mph), according to the weather agency.

About 20 storms and typhoons batter the Philippines each year. The archipelago also lies in the “Pacific Ring of Fire,” a region along most of the Pacific Ocean rim where many volcanic eruptions and earthquakes occur, making the Southeast Asian nation one of the world’s most disaster-prone.

In 2013, Typhoon Haiyan, one of the strongest recorded tropical cyclones in the world, left more than 7,300 people dead or missing, flattened entire villages, swept ships inland and displaced more than 5 million in the central Philippines — well to the south of Noru’s path.