Two people were killed when a schoolbus mounted a pavement in a crowded Hong Kong neighbourhood on Monday, trapping passers-by underneath and injuring 13, police said.

An elderly woman and a man were killed after the yellow schoolbus ran over a pavement in the downtown North Point district, with photographs in local media showing victims sprawled on the ground while others received medical treatment at the scene.

The vehicle rolled down the street after it was parked, terrifying passers-by as the driver ran towards it and tried in vain to stop it, the South China Morning Post reported, citing an online video clip.

It crashed into a building in a narrow lane lined with shops as stationery and toy guns spilled onto the bloodstained street.

At least four people were left in a coma, a police spokesperson told AFP.

Hong Kong prides itself on having one of the world's best public transport systems but deadly bus accidents are not unknown.

Five people were killed and 32 injured when a coach carrying Cathay Pacific staff to Hong Kong's airport collided with a taxi last month.

A speeding double-decker overturned in northern Hong Kong in February, killing 19 people and leaving more than 60 injured. The bus driver was arrested for dangerous driving.

And in 2003 a double-decker bus collided with a truck and plummeted off a bridge, killing 21 people and injuring 20.

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