WASHINGTON (AP) — Republican presidential candidate Ted Cruz is apologizing for cracking a joke at Vice President Joe Biden’s expense even as Biden mourns the death of his son.

During an appearance Wednesday in Howell, Michigan, Cruz rattled off a Biden line he’s been using in speeches on the stump. In the joke, Cruz pokes fun at Biden’s occasionally controversial remarks and tells his audience that one need only mention Biden’s name to get people to laugh.

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By Thursday morning, Cruz used his Facebook account to say he was sorry.

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In his post, the Texas senator says, “It was a mistake to use an old joke about Joe Biden during his time of grief, and I sincerely apologize.”

A funeral Mass will be held in Delaware Saturday for 46-year-old Beau Biden.

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