The woman found dead onboard a boat in Montauk on Tuesday was identified by authorities as a beloved local designer from Manhattan who spent her summers working on the East End. Martha Nolan-O'Slatarra was found unconscious on a vessel docked at the Montauk Yacht Club at approximately 12 a.m., according to Suffolk County police. The 33-year-old, who went by Martha Nolan professionally and in social circles, was pronounced dead at the scene by first responders. Her cause of death is still under investigation and will be determined by the Suffolk County Medical Examiner's Office. Members of the Montauk Yacht Club, including some captains, heard screaming from the docks late Monday, one club member told The Post. Another anonymous member of the yacht club remembered Nolan fondly. "She was well known in the community. She was very friendly. Always smiling," the person said, adding, "There's going to be a lot of conversation out of this." Nolan was a marketing consultant, entrepreneur, and founder of fashion brand East x East, according to herLinkedIn. The Ireland native moved to the US at the age of 26 and started launching pop-ups with her summerwear brandEast x Eastin the Hamptons in 2023, she told theIrish Independentin a profile last year. Montauk residents told The Post that Nolan had a reputation for being incredibly kind and was always equipped with a bright smile. Just last month the businesswoman celebrated a pop-up shop at Montauk's exclusive spa, the Gurney's Resort. "Goals Achieved," she captioned in a July 1post on TikTokthat showed off her swim-, eye-, and resort wear at the club. Crime scene investigators remained at the Montauk Yacht Club late into the night with a van from the Suffolk County Crime Laboratory and a command post parked past 9 p.m. Tuesday. The Suffolk County Police Homicide Squad is investigating the incident, according to the release. This is a breaking story. Please check back for updates.