When the sun rises on April 1, you can't trust anyone — not even Tool.

The band pranked fans with a Facebook post decrying the supposed leak of a song from its long-gestating follow-up to 2006's 10,000 Days LP, calling it "unsettling on many levels" and accusing another band of turning around and posting the stolen song as their own work.

"First off, it truly sucks to have your unfinished music available on the interweb without your consent. And second, to have it immediately picked up by someone and released as their own work is infuriating," reads the note. "We don't encourage anyone to listen to this leaked clip because it's far from finished and it will spoil what's to come. But if you absolutely must, then listen to both clips. These are practically identical. It's a clear cut case of copyright infringement and plagiarism."

The post, which concludes with the hashtags #‎sue everybody‬ and ‪#‎marchthirtysecond‬, points to a pair of YouTube links, the "Tool Leak" and "The Other One" — both of which play "El Sondito," a massive 2009 hit for the Mexican group Hechizeros Band.

Unsurprisingly, a number of the long-suffering fans who commented on the post failed to find the humor in the joke, but it's hard to find fault with the members of Tool for wanting to blow off a little social media steam; after all, progress on the new album has been painfully slow due to a lawsuit that's dragged on for years — and as guitarist Adam Jones told Rolling Stone last month, a member of the band was even hit with "a really scary do-or-die, serious illness."

But according to Jones, that's all in the past, and the band now has one song completed with 10 others waiting for finishing touches. "Things are progressing nicely. Slowly, but definitely progressing," wrote singer Maynard James Keenan in February. "I'm as anxious to get this album completed as everyone else. But as history will show, you can't rush these gents."

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