About 75% of homes in Bohol province in the Central Visayas region are damaged, Casiano Monilla, assistant secretary at the Office of the Civil Defense, said at a news conference Monday. At least 227 cities and municipalities experienced power outages and 25 flights were canceled, he added.

The estimated cost of damage is more than $4.5 million, Monilla said.

Aerial photos released by the Philippine Coast Guard reveal the extent of damage in Negros Occidental province in the Western Visayas region. Roads and fields can be seen flooded for miles in each direction after the heavy rain.

Workers have been wading thigh-deep through floodwaters to evacuate citizens from disaster-stricken areas. Around 332,000 people have been evacuated from their homes, a spokesperson from the National Disaster Risk Reduction and Management Council said on Friday.

The storm hit several heavily populated areas, including Cebu, a city of nearly 1 million people.

More than 30 transmission lines were down in the Visayas and Mindanao -- two of the country's three major island groups and home to a combined population of more than 45 million.

Many buildings were destroyed across several badly affected areas. Residents were seen scrambling through mud and debris to salvage whatever they could from their damaged homes.

Rai was the 15th storm to hit the the Philippines this year. It decreased in intensity and is now a typhoon with maximum winds of 165 kilometers (103 miles) per hour, equivalent to a Category 2 storm.

The storm is now off the coast of Vietnam in the South China Sea and is expected to weaken further as it gets closer to Hainan, China within the next 24 hours.