Horror metal legend King Diamond has been forced to withdraw from Mexico's Hell and Heaven Metal Fest after experiencing a slower recovery from surgery than expected.

The news was made official on social media where the 63-year-old singer outlined some loose details about his surgery. He was, however, reluctant to disclose what type of surgery he was currently recovering from, noting that it was necessary if he wished to continue to be able to travel by plane, a very necessary component of his career.

"I was recently advised by my doctor to have surgery done for an issue, which, if not done right away, would have prevented me from flying," King Diamond began in his statement.

"We did not expect to have any complications after the surgery, but my healing is slower than anticipated, and I've been advised to 'forego air travel until his healing stabilizes and additional risks are minimized,'" the frontman continued, lamenting his withdrawal from the fest as he added, "Unfortunately and regretfully, this means that we cannot make it this weekend to play at the Hell & Heaven [Metal Fest]. We love playing in Mexico and can't wait to get a chance to make this up to you. Til then, stay heavy."

King Diamond is no stranger to the operating room, having undergone open heart triple bypass surgery a decade ago.

A new album from the King, The Asylum, is expected to be released some time this year and will mark the first release from the group since 2007's Give Me Your Soul... Please. Listen to the debut album single "Masquerade of Madness" here.

Mercyful Fate, King's other band, have also reunited and are working on new material as well.

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