Police are pressing three charges, including a drug offence, against a driver who failed to overtake a lorry and plunged his double-decker bus off a winding Nakhon Ratchasima road, killing 18 passengers.
An earlier claim by Kritsana Chuthachuen, 45, who blamed "brake failure", was groundless, causing the officers to also accuse him of driving carelessly causing death and fleeing the scene without helping passengers, Provincial Police Region 3 chief Damrongsak Kittipraphat said yesterday.
Another 32 of the 50 passengers were left injured on the side of Road No.304 after the bus hit roadside stalls and trees in Wang Nam Khieo district.
The victims were returning to Kalasin from Chanthaburi when the accident occurred on Wednesday night.
Mr Kritsana turned himself in to the police on Thursday.
Experts who examined the bus's braking system found no trace of oil leakage. This suggested the crash should not have resulted from brake failure, Pol Lt Gen Damrongsak said.
Mr Kritsana admitted to police he drove at a "rather high speed" and wanted to overtake a sugarcane-loaded truck in the left lane.
But he lost control of the bus, smashed through the central barriers and crashed on the opposite side of the road.
The bus's global positioning system showed the bus was traveling at 83km per hour. This exceeded the legal limit of 60kph, Pol Lt Gen Damrongsak said.
Mr Kritsana also tested positive for drug use. He told police he took speed pills twice during the trip.
A further check found he had faced drug charges five times between 2002 and 2013, Pol Lt Gen Damrongsak said.
According Pol Lt Gen Damrongsak, the company was legally required to have the bus checked twice a year, but the vehicle has not been tested in over a year.
Investigators are gathering evidence to determine whether they will charge the company, Pol Lt Gen Damrongsak said.
