The Longshot, a side project of Green Day frontman Billie Joe Armstrong, have postponed the remainder of the West Coast leg of their tour. The reason is a "very serious family emergency" involving a member of the band.

"One of our band members @longshot is dealing with a very serious family emergency," Armstrong wrote on Instagram last night. "It’s with heavy hearts we need to announce tonight’s show in Santa Ana and the rest of the west coast shows will be postponed. We love you all and we will be back. Please send good vibes to each other."

The Longshot was scheduled to play at Rickshaw Stop in San Francisco tonight, with four more dates -- in Seattle, Bellingham, Wash., Vancouver and Portland -- booked through May 15. As of now, they are still scheduled to play on the East Coast, beginning May 22 in New York and running through June 2 in Philadelphia.

Armstrong debuted the Longshot last month at a club in Oakland, only a few days after releasing a three-song EP. A week later, he put out those songs, along with eight others -- including a cover of Ozzy Osbourne's "Goodbye to Romance" -- on an album, Love Is for Losers.

He's the only credited musician on the LP, besides his drummer son, who appears on one track. Armstrong announced the news of the record with an Instagram post. "The new Longshot album is officially out!!" he wrote. "Hit the link! Let’s party! Get naughty! Do some bad things!! Get loaded! Fuck the world it’s judgment day!!"

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