The search for a missing 55-year-old swimmer was indefinitely suspended at Lovers Point on Monday evening, according to a joint media release from officials. The missing woman was identified as Erica Fox, a co-founder of the Kelp Krawlers swimming group who helped start the group 20 years ago, according to a current member of the group and as reported by Monterey County Weekly.Pacific Grove police said the woman was swimming with a regular group that meets in the area every Sunday. “I’m in shock, and I’m kind of numbed by all this, because it was just out of the blue,” Erica's father, James Fox, told NBC News on Monday. “Erica was doing something yesterday that she really loved.”Investigators said the group entered the water as usual, but around noon, a witness on the shoreline reported seeing a “large splash.”Police said the sight prompted the other swimmers to head back to shore out of concern it may have been a shark attack. Everyone in the group returned safely except Fox.Two witnesses said the swimmer may have encountered a shark while swimming offshore near Lovers Point.According to the U.S. Coast Guard, the first report came from a driver stopped at a stop sign. The witness said they saw a shark breach the water with what appeared to be a human body in its mouth. The witness then saw the shark submerge below the waterline and not resurface.The Coast Guard said a second witness, a member of the swim group, took a count and realized Erica Fox was missing.She was described as a 55-year-old woman with blue eyes, wearing a red bathing suit and a yellow swim cap. The search was suspended on Monday afternoon, after 15 hours of searching an area of more than 84 square nautical miles.“The Coast Guard extends its deepest condolences to the family, friends, and loved ones affected by this tragic incident,” said Captain Jordan Baldueza, Coast Guard Sector San Francisco commander.Multiple agencies joined the response, including the U.S. Coast Guard, Monterey Fire Department, Seaside Fire, and CAL FIRE. Authorities said crews have been using rescue boats, drones, and helicopters to search the water and the surrounding area.“While coordinated search operations have concluded, detectives will continue to investigate the circumstances surrounding the disappearance,” said Commander Brian Anderson, Pacific Grove Police Department. “We remain committed to determining what happened and following every available lead.”Lovers Point Beach in Pacific Grove, and McAbee and San Carlos beaches in Monterey, will remain closed through Tuesday. A beach advisory will remain in effect for Asilomar State Beach, Monterey Municipal Beach, Del Monte Beach, and Monterey State Beach through Tuesday as well.Erica Fox is a swimmer and triathlete who has done two half-Ironmans and numerous other triathlons and who, for almost 20 years, did an annual triathlon called Escape From Alcatraz, her father told NBC News."Swimming was her forte. She just loved that," James Fox said to NBC News.See more coverage of top Central Coast stories | Download our app / Subscribe to our morning newsletter | Find us on YouTube here and subscribe to our channel