Vingegaard suffers broken collarbone after 'terrible' crash in Basque Country
"It was a terrible fall but thankfully he is in a stable condition and conscious," his team Visma-Lease a Bike reported on X.
"Tests in hospital have revealed that he has suffered a broken collarbone and several ribs. He remains under supervision at the hospital," the team added on the social media platform.
Belgian ace Remco Evenepoel was another to emerge battered and bruised from the horror accident.
"Remco will return to Belgium tomorrow to be operated on a broken collarbone and pass further tests at the hospital at Herentals," his Soudal-Quick Step team announced.
His injuries have ruled him out of upcoming one-day classics in the Netherlands and Belgium.
Other big names involved in the crash who were taken to hospital were Jay Vine and Steff Cras, while Primoz Roglic was also involved and did not finish the stage.
"Over the radio we heard that Jonas was involved in a big crash," said Visma sports director Addy Engels. "We immediately saw that it didn't look good when we arrived to him."
Despite the gravity of Vingegaard's injuries they came as almost a sense of relief that they were not more serious.
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.
The 2022 and 2023 Tour de France winner Vingegaard was taken to an ambulance on a stretcher, while Belgian Evenepoel was walking but his team Soudal Quick Step confirmed he was also going to hospital.
"Jonas is conscious and will be examined in the hospital now," Visma said at the scene.
"Thank you for your messages. More updates later," they added of their 27-year-old star who won the Basque Tour last year.
Last week Visma rider Wout van Aert suffered identical injuries in another bad crash at the Dwars door Vlaanderen one-day race.
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 injured.
UAE Team Emirates said their Australian rider Vine was also taken to hospital but was conscious and talking, along with Team TotalEnergies rider Cras.
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.
"Horrified by the crash we witnessed today. Our team was spared, but we feel for those who got caught," said team Decathlon-AG2R on X.
"We can only wish that all riders involved are not injured too seriously."
'Stage times not counted'
A six-man breakaway was allowed to continue to try and race for the stage win in the final 18km, with Louis Meintjes crossing the line first.
"The race is neutralised until the finish line, the six leading riders will compete in the stage but the stage times will not be counted for the general classification," race organisers said.
"The bunch will go in neutral until the finish line."
Meintjes finished ahead of second place Reuben Thompson and Vacek Karel in third.
"It's not the way you want to win... if there was a challenge for the break I would have been ready to fight for the stage," South African Intermarche-Wanty rider Meintjes told Eurosport.
"(What happened) is unfortunate, takes the pleasure out of it, it's maybe a victory but it doesn't feel like it.
Earlier Thursday Roglic's team-mate Lennard Kamna was 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.
Friday's fifth and penultimate stage is a 175.9km ride north from Vitoria-Gasteiz to Amorebieta-Etxano.