Marvel creator Stan Lee was reportedly hospitalized this week after experiencing a shortness of breath and an irregular heartbeat, TMZ reports.

Sources said the 95-year-old comic book legend was admitted to Cedars-Sinai Medical Center in Los Angeles on Wednesday following an unspecified illness. Though he is still at the facility, he said to be in stable condition.

“[Lee] is doing well and feeling good, he is staying there for a few days for some check ups as a safety precaution,” a spokesperson told the publication. 

According to TMZ, Lee had canceled multiple convention appearances in 2017 due to reported health issues; however, he has never revealed the details of the ailments. He later went to Facebook to reassure fans he was making a good recovery: Been feeling almost back up to snuff. So time to send out the battle cry: EXCELSIOR!"

Though Lee appeared to be in good spirits during the Hollywood premiere of Black Panther on Monday, the former editor-in-chief of Marvel Comics has been at the center of controversy following a number of sexual misconduct allegations

Several of Lee’s home nurses claimed he had repeatedly groped them, demanded oral sex, walked around naked in front of them, and asked to be “pleasured.”

Lee’s lawyer Tom Lallas has since sent a cease-and-desist to the nursing company that employed the nurses.

“Mr. Lee categorically denies these false and despicable allegations, and he fully intends to fight to protect his stellar good name and impeccable character. We are not aware of anyone filing a civil action, or reporting these issues to the police, which for any genuine claim would be the more appropriate way for it to be handled,” Lallas told the Daily Mail. “Instead, Mr. Lee has received demands to pay money and threats that if he does not do so, the accuser will go to the media. Mr Lee will not be extorted or blackmailed, and will pay no money to anyone because he has done absolutely nothing wrong.”