At least 17 people were killed this weekend when a passenger bus plunged off an elevated highway in Manila and fell onto of a passing van, according to the Associated Press.

Some 16 others were injured during the incident, and video footage showed that the van was basically unrecognizable after the fall.

The bus supposedly drove off the Skyway and crashed onto the van approximately 32 feet below at around dawn, said police Superintendent Elizabeth Velasquez.

Police have not been able to figure out what caused the accident, but witnesses have said that the highway was wet from rain.

Irene Sisperes, a motorist who witnessed the accident, estimated that the bus was moving at speeds between 62 mph and 68 mph.

"After a few meters, I saw the bus fall and I shouted, 'The bus fell, the bus fell'," said Sisperes to DZMM radio.

No other cars were nearby fortunately.

Earlier reports indicated 21 died and 20 others were injured but later said there appeared to have been "double counting," according to police Superintendent Elizabeth Velasquez.

Angelo Dequina, an employee of a funeral parlor, said 17 bodies from the accident were brought to their mortuary from hospitals and from the crash site.

At least 16 people were taken to five different hospitals, according to the Associated Press.

The bus driver was "critically injured" during the incident, but the van driver suffered minor injuries, Velasquez said.

In 2011, a bus from another company fell from the Skyway near the same location. The incident left three people dead and four injured. 

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