A man was killed and six other people, two of them children, were seriously hurt in a head-on collision between two cars in Bradford.
The 87-year-old man, a passenger in a Suzuki Alto, was declared dead at the scene near the Haworth Road junction shortly after 1400 GMT on Sunday.
The driver and other passengers, including the children, were being treated at Leeds General Infirmary.
Two men in a Vauxhall Vectra were taken to Bradford Royal Infirmary.
West Yorkshire Police said one of the men travelling in the Vectra had been arrested on suspicion of causing death by dangerous driving.
The driver of the Alto, a man in his 30s, was airlifted to Leeds General Infirmary with serious head injuries.
The children are aged eight and four.
A force spokesman appealed for witnesses. Accident investigators are at the scene.