Billy Joel has married in a surprise ceremony.

The 66-year-old musician tied the knot with Alexis Roderick on Saturday evening, his representative has confirmed. The ceremony wasn’t just a shock for his fans – even those close to Billy didn’t know what he had in store.

“[The couple] surprised guests at their annual July 4th party by exchanging vows in front of their family and close friends,” the spokesperson explained to People.

The wedding took place at Billy’s home in Long Island, with his friend Andrew Cuomo – the governor of New York – officiating.

Exactly how many people attended isn’t known, but it’s thought just a clutch of close family and friends saw the pair marry. Among the guests was Billy’s daughter Alexa Ray and actor Kevin James.

Billy and Alexis, 33, have been together since 2009 and are preparing for the arrival of their baby girl later this year.

The pair confirmed the news in April, with Billy discussing how excited he is to become a father again.

“I'm probably going to be able to spend more time with this kid than most people are able to spend with their children, because I don't have a regular job,” he previously told Newsday. "I could be a stay-at-home dad for as long as I can stay alive.”

This is the fourth marriage for Billy, who was previously wed to Elizabeth Weber Small, Christie Brinkley and Katie Lee.