A car crash in a suburb of Gisborne has claimed the lives of four.

Ormond's Matawai Road saw two cars collide, with three in one car killed, and one taken to hospital, according to emergency services.

A spokesperson from the Gisborne fire station said police are further investigating the accident.

According to one witness, one of the cars caught fire in the crash.

This pushes the long weekend's road toll to six.

A pregnant woman was also killed, and four hospitalised after a crash north of Timaru yesterday afternoon.

The two-car crash occurred just before 3pm today and forced police to shut down part of State Highway 1 near the intersection with Divans Rd, 5km north of Timaru.

A car on Divans Rd pulled out onto SH1 and the vehicles collided.

A pregnant 24-year-old Timaru woman was killed as a result and her husband, who was the driver, was thrown from the vehicle, sustaining serious injuries.

Their two children, aged 4 and 5, were in the back seat and have been treated for minor injuries.

Three St John ambulances were sent to the scene, a spokesman said.

Four passengers were taken to Timaru Hospital, including one with critical injuries and one with very serious injuries.

Police were tonight still diverting traffic from the highway but said no other details were available.

Annalese Bacon, 17, died on Friday night when the driver of the car she was travelling in lost control and the vehicle flipped in Reporoa

The official holiday period for Labour Weekend 2012 began at 4pm 19 October and ends at 6am Tuesday 23 October.

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