Speeding was said to be the cause of the bus accident in Muar that killed 14 people after it plunged into a ravine early Saturday morning.

Muar district police chief Assistant Commissioner Azman Ayob said the bus skidded towards the left side of the expressway and left marks on the road trailing about 150 metres.

"The bus was believed to have skidded towards the left side the expressway and plunged into ravine about eight to 10 metres deep.

"The location of the accident was Kampung Jayo, Pagoh. 14 had died, where 13 of them were killed at the location of the accident and another while on his way to the Muar Hospital," he told a press conference at the Muar District Police Headquarters today.

He said the accident that occurred at around 3.45am, did not involved other vehicles.

According to Azman, the Aliran Golden Coach Express bus was en route to Kuala Lumpur from the Larkin Bus Terminal in Johor Bahru.

He said after the bus skidded, it plunged into a 10 metre-deep ravine before crashing into a concrete wall in Kampung Jayo, Pagoh.

The impact of the collision caused 13 of the 30 passengers to die on the spot.

READ: 13 killed, 17 injured in bus accident in Muar

READ: Another passenger dies in Muar bus crash

The injured passengers comprise of seven Malaysians, six Singaporeans, two from Myanmar and one person of unverified nationality.

Azman said the case was being investigated under Section 43 (1) of the Road Transport Act 1987.