GOA: Four labourers were killed and five others critically injured when a private bus rammed into two roadside shanties at an industrial estate in South Goa district, the police said on Sunday.

The accident took place at around 11.30 pm on Saturday at the Verna Industrial Estate when the labourers, engaged in road construction work, were sleeping in the shanties, they said.

The bus driver has been arrested, the police said.

A labourer claimed the bus driver was under the influence of alcohol at the time and threatened the other labourers to kill them if they complained to anyone about the incident.

The bus carrying staff of a private company hit two shanties where labourers were sleeping, a police official said.

"Four labourers died on the spot while five were critically injured and admitted to the Goa Medical College and Hospital," he said.

The labourers were employed by a contractor, the police said.