UPDATE, 3:29 p.m., Tuesday, Jan. 22: Francesca Ambrose, Olivia’s twin sister, confirmed with MassLive that sister had been found alive on Tuesday.

Boston police are investigating the disappearance of a 23-year-old woman who has not been seen since Saturday night.

Olivia “Liviy” Ambrose, a 23-year-old Wenham native who recently moved to Jamaica Plain, disappeared after a night out in Boston Saturday night, according to friends and family.

Ambrose’s twin sister, Francesca, said the two were out with a large group of friends, some from college and others from their volleyball team, at Hennessy’s in Boston on Saturday night before Olivia went missing.

Francesca and friend Kate Collins said they last saw Olivia around 10 p.m., when they were all dancing together inside the Union Street pub that hosts live music.

“We were all dancing in front of the stage, nothing out of the ordinary,” said Collins, who has worked with Francesca for several years. “There were a lot of other friends.”

Olivia then walked outside with a man who had been escorted out of the bar by a bouncer, according to Francesca. Surveillance footage reveals the pair left around 11:05 p.m., and loved ones say Olivia has not been seen or heard from since.

According to her sister, the location of Olivia Ambrose’s iPhone 8 last pinged near Walford Way and Corey Street in Charlestown, near a Boston Housing Authority complex.

Boston Police identified and contacted the man Olivia left with that evening, according to a Facebook post by Francesca shared Monday afternoon. He has not been publicly identified.

Francesca asked the public to now turn their attention to locating her sister instead of trying to identify the man in the surveillance photos.

Family and friends said they have visited Olivia’s Jamaica Plain apartment twice since she went missing in the hopes of finding her, but she was not there.

Olivia has blue eyes, curly brown hair and a height of about 5 feet 2 inches, according to authorities. She was last seen wearing a white or beige coat with a red corduroy dress and Dr. Marten boots.

Olivia works at Toast, Inc. and is a graduate of the University of Edinburgh.

The family filed a missing person’s report with Boston Police on Sunday afternoon for a woman last seen at 25 Union St. The Boston Police Department confirmed on Monday that they were conducting an open and active investigation to locate Olivia. Authorities are urging anyone with information to contact 911 or District A-1 Boston Police Detectives at (617) 343-4248.

This story has been updated to reflect the most recent information.