A Swaziland rights group says 38 girls and young women were killed in a crash while travelling to a famous traditional festival.

The Swaziland Solidarity Network said in a statement on Saturday that about 20 others were injured when the truck they were in collided with another vehicle on Friday.

The Times of Swaziland reported that the truck smashed into the back of a van and was then hit in the rear by another truck.

The women were on their way to the Swazi king's royal residence for the annual reed dance.

A government website says about 40,000 girls and young women participate in the eight-day ceremony each year in which they bring reeds to reinforce the windbreak around the royal residence.