Police are appealing for witnesses following a serious collision on Horsforth New Road near Rodley.
Officers would like to speak with anyone who witnessed the collision between a Vauxhall Vivaro van and a Toyota Auris on the A6120 Ring Road between Calverley and Rodley at about 4.55pm on Monday, February 12.
It took place after the Vivaro, which was travelling northbound, was in a head-on collision with the Toyota travelling in the opposite direction.
A four-month-old baby in the Toyota suffered life threatening injuries in the incident and was taken to hospital, where he remains today.
Two women from the Toyota and a man from the Vivaro were also taken to hospital.
The male driver the Vivaro has now been arrested on suspicion of causing serious injury by dangerous driving.
A full road closure was put in place at the location while emergency services managed the incident.
Anyone who saw or has footage of the collision is asked to contact the Eastern Area Roads Policing Unit on 101 referencing police number 13240081077. Information can also be given online at www.westyorkshire.police.uk/livechat.
Police issue appeal after crash leaves baby with life-threatening injuries
