ET reported over the weekend that Joe Manganiello had to pull out of a charity event on Sunday due to a “health issue,” and now it appears there might be another, or more serious condition that he's dealing with.

According to TMZ, the 39-year-old Magic Mike star was admitted to a hospital late last week and underwent surgery to have his appendix removed. TMZ called the surgery "extremely serious," and reported that doctors were "alarmed" by Manganiello's condition.

WATCH: Joe Manganiello Drops Out of Charity Appearance Due to Unspecified Health Issues

Manganiello's rep had no comment when ET reached out for a response to the TMZ report.

Manganiello and his wife, Sofia Vergara, were expected to act as honorary co-chairs at the Stuart House Benefit in West Hollywood, California, to raise funds for the facility, which helps children and families recover from sexual abuse. A representative at the event told ET that the actor dropped out due to "health issues."

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On Sunday afternoon, Manganiello tweeted a short message, writing, "I love my wife."

Last week, the True Blood alum also had to bow out of History Channel's Navy SEAL drama series Six, reportedly for health reasons and the physical demands of the series.