Though there is no official confirmation, the friend says, "It happened earlier this evening. Jay wanted it to be a really private affair – close friends and family."
The ceremony was followed by a lavish party at the rapper's Tribeca apartment that drew Beyoncé's mother Tina Knowles, her father/manager Mathew, her sister Solange, her Destiny's Child mates Kelly Rowland and Michelle Williams, and the couple's friend Gwyneth Paltrow.
(See photos of the guests arriving here.)
The wedding buzz began when the couple went to get a marriage license at a village hall in Scarsdale, N.Y., on Tuesday.
DJ Cassidy, a favorite of Jay-Z, was hired to spin. "Cassidy mentioned a week ago that he was really excited for Jay Z and Beyoncé's wedding party to happen," says another source.
Early Friday morning, workers erected a white tent atop the building in Tribeca, where Jay-Z owns a penthouse apartment. Not long after, an SUV carrying what seemed to be AV equipment arrived, followed by deliveries of party rentals and flowers.
A source tells PEOPLE that Amy's Orchids was hired to provide 50,000 to 60,000 white orchid blooms from Thailand for a "big party." At the apartment, waiters were seen practicing their service.
A couple since 2002, Jay-Z, 38, and Knowles, 26, always kept quiet about their relationship, even as they were photographed together on romantic holidays around the world.
Still, marriage seemed to be in the cards – eventually. "I never pictured myself as a bride," she told Cosmopolitan in January 2006, "but after my sister's wedding, I did start thinking about what kind of wedding I'd want. I don't think I want a big one."
Isabella Dickerson / Splash News Online
Reporting by RYAN PIENCIAK, TIFFANY McGEE, MELODY WELLS and LESLEY MESSER
See Photos: Power Couple in Love
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