The singer finally left U.S. customs after four hours

Update: Justin Bieber is back on American soil.

According to reports, the singer was released after being detained by customs on Thursday for nearly four hours in Los Angeles.

"All smiles," Tweeted the Biebs, along with a photo of himself.

"That was a long day. Bring on Friday," Tweeted his manager Scooter Braun.

No kidding.

Yesterday, E! News says officials questioned Bieber "for the last two hours inside the airport's Tom Bradley International Terminal," with the pop star's entourage "standing around waiting for him."

TMZ says "it's all because of his string of legal troubles."

According to People, he was being held "for routine secondary questioning" but "was not being kept out of the United States."

The pop star is juggling legal woes. He's scheduled to go on trial in Miami in July on charges of driving under the influence and resisting arrest. A misdemeanor assault case in Toronto is awaiting trial, and in Los Angeles, prosecutors are considering whether to bring a felony vandalism case against him over eggs thrown at a neighbor's house.

Bieber was on his way back to the U.S. after returning from a recent trip to Asia (which had its own bumps) and flew Singapore Air, landing at 1 p.m. PST, according to Us Weekly.