During the second stage of the Tour de France, tacks were thrown onto the road near the base of the Jaizkibel, causing many sudden punctures; 15 to 20 riders were forced to stop to change wheels or ride to the finish with slow punctures or tacks in their tires.

It is unclear who threw the tacks into the road and why. There were no signs of protests during the stage as cycling-mad Basque fans cheered the riders on the 208-km section from Vitoria to San Sebastián.

Race organizer ASO told Cycling News that they were aware of tacks on the road, but had no further information.

Race radios reported numerous punctures in the last 20 km of this stage, and teams were busy servicing riders during this critical phase of the race.

French rider Lilian Carmejanet exploded on social media in anger over the tacks on the road, posting a video counting the five tacks stuck in his front wheel: "Thanks for this human crap ....... I don't think I'm the only one who got hit by a flat tire in the finals... I don't think I'm the only one who got hit with a flat tire in the finals...

The Jayco-ALUla team confirmed that Luke Durbridge was the victim of a puncture, showing a wheel with two tacks in it. Cofidis also suffered a number of punctures, but Victor Lafaye was unaffected, helping the French team to a stage win.

Tom Pidcock suffered a slow puncture, but said he was able to ride to the finish despite losing control. Ineos Grenadier was using tubeless tires and the sealant that slowed his puncture was visible in his rear wheel as he warmed down on the roller stand.

"It was a slow puncture and I could feel it on the descent of Jaizkibel. I could feel it sliding a little bit in the corners," Pidcock told Cycling News and ITV TV in the shadow of the Ineos Grenadiers team bus.

Matt White, head of performance for Jayco Aroura, admitted that the tack caused major problems for the peloton.

"In one town someone sprayed tacks on the road. Some riders got punctures right away, others had slow leaks. It's a shame. We were lucky that Simon Yates didn't get a puncture, but so many riders got punctures at a crucial time in the race."