Two-time Tour de France champion Jonas Vingegaard and Remco Evenepoel were taken to hospital after a mass crash also involving Primoz Roglic, which resulted in stage four of the Tour of the Basque Country race being paused on Thursday.

Several of the 12 riders involved in the crash fell into a concrete ditch after sliding off on a corner with around 35 kilometres to go in the run from Etxarri Aranatz to Legutio, in northern Spain.

Danish rider Vingegaard was taken to an ambulance on a stretcher, while Evenepoel was walking but his team Soudal Quick Step confirmed he was also going to hospital.

Roglic, who also abandoned the race, offered a thumbs up to television cameras while sitting in the Bora-Hansgrohe team car, to show he was not significantly harmed.

The crash happened on the descent from the Alto de Olaeta after a rider in the front of the peloton slid off the road on a right-hand bend.

Earlier Thursday Roglic's team-mate Lennard Kamna was left in a "stable condition" in intensive care after a collision with a car during a training ride in Tenerife.

Roglic, who also fell on Wednesday in stage three but quickly recovered, was leading the overall standings from Evenepoel by seven seconds at the start of racing on Thursday.

Update:

Vingegaard was "conscious" after being taken to hospital following a mass crash in stage four of the Tour of the Basque Country race, his team said Thursday.

"Jonas is conscious and will be examined in the hospital now," Visma Lease a Bike said of the Danish rider, one of several taken to hospital after the incident, along with Remco Evenepoel and Jay Vine.