At least three people have been killed and hundreds of thousands have been forced to flee their homes as Typhoon Kalmaegi ripped through the central Philippines, according to the country's disaster agency.

The typhoon flooded large areas, including entire towns on the island of Cebu. Videos from the area show people sheltering on rooftops, while cars and shipping containers have been swept through the streets.

In an unfortunate twist, a military helicopter deployed to assist relief efforts crashed in northern Mindanao island, with reports still pending regarding potential survivors.

The storm, known locally as Tino, has weakened since making landfall early Tuesday but continues to produce winds exceeding 80 mph (130 km/h). It is expected to move across the Visayas islands region and out into the South China Sea by Wednesday.

The situation in Cebu is really unprecedented, said provincial governor Pamela Baricuatro in a Facebook post. We were expecting the winds to be the dangerous part, but... the water is what's truly putting our people at risk. The floodwaters are just devastating.

Residents like Don del Rosario, 28, who took refuge on an upper floor, described the experience as the worst in his 28 years of living in the area.

According to the Office of Civil Defence, almost 400,000 people have been moved from the path of the typhoon.

The Philippines typically endures around 20 storms and typhoons each year. This latest destruction follows closely after back-to-back typhoons that wreaked havoc last month, claiming over a dozen lives and causing severe damage to infrastructure and agriculture.

In the lead-up to the storm, an exceptionally wet monsoon season had already resulted in widespread flooding and rising discontent over inadequate flood control systems, which are often blamed on corruption.