A passenger bus has veered off a road and plunged into a precipice in a mountainous region in Sri Lanka, killing 15 people and injuring 16 others.

The accident occurred near the town of Wellawaya, about 280km east of the capital Colombo, on Thursday night and the bus fell into a roughly 300-metre precipice, police spokesman Fredrick Wootler said.

The accident killed 15 people and wounded 16, including five children.

Wootler said an initial police investigation revealed the driver was driving the bus at high speed and lost control of it, crashing with another vehicle and into guardrails before toppling off the cliff.

At the time of the accident, nearly 30 people were travelling on the bus.

Local television showed footage of the severely damaged bus lying at the bottom of the precipice

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