Charlie Sheen Charlie Sheen

How's this for a Father's Day tribute to the mother of your children?

Charlie Sheen spent some time on Sunday hurling offensive insults at his ex Denise Richards via Twitter, calling her (among other things) "a washed-up piglet Shame pile," an "evil terrorist sack of landfill [trash]" and "worst mom alive."

Sheen has since deleted the tweets, but a longer (NSFW) rant about Richards can be seen here.

The diatribe seems to have been sparked by Richards referring to Sheen as a "deadbeat dad."

Read Jon Cryer's inside account of Charlie Sheen's meltdown

As far as his other ex-wife, Brooke Mueller, Sheen referred to her as a "sexy [rock] star whom I adore."

Richards filed for divorce from Sheen in 2005 after three years of marriage. They have two daughters together.

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