By Gregory Krieg and Jeff Zeleny, CNN

Sen. Bernie Sanders experienced “chest discomfort” on Tuesday night and will suspend campaigning “until further notice” after doctors treated a blockage in an artery, senior adviser Jeff Weaver said in a statement Wednesday morning.

“Following medical evaluation and testing he was found to have a blockage in one artery and two stents were successfully inserted,” Weaver said. “Sen. Sanders is conversing and in good spirits. He will be resting up over the next few days. We are canceling his events and appearances until further notice, and we will continue to provide appropriate updates.”

Weaver delivered the news about the senator’s health during a conference call around 10:30 a.m. ET, an aide told CNN. He read the statement that was later released and did not elaborate.

Sanders, who is 78 years old, felt the “discomfort” during a campaign event. Despite his age, he has been one of the most active campaigners in the 2020 Democratic primary field.

Minutes after the news of Sanders’ procedure became public, his campaign rivals responded with an outpouring of support.

“Bruce, Team Warren, and I are sending all our best wishes for a speedy recovery to @BernieSanders,” Sen. Elizabeth Warren, one of Sanders’ closest allies in Washington, tweeted. “I hope to see my friend back on the campaign trail very soon.”

South Bend, Indiana, Mayor Pete Buttigieg also wished Sanders well.

“All of us here at @PeteForAmerica are sending our best wishes for a speedy recovery to Senator @BernieSanders,” Buttigieg tweeted. “We’re thinking of him and his family today, and I look forward to seeing him back on the campaign trail very soon.”

And former Vice President Joe Biden tweeted, “.⁦‪@DrBiden‬⁩ and I are sending our best wishes to ⁦‪@BernieSanders‬⁩, Jane, and the whole Sanders family. Anyone who knows Bernie understands what a force he is. We are confident that he will have a full and speedy recovery and look forward to seeing him on the trail soon.”