Three individuals remain missing and are feared dead after a private pleasure craft carrying 20 people sank in San Francisco Bay on Tuesday afternoon, with a survivor suggesting they may have been trapped inside the vessel as it submerged. The incident occurred around 3:30 p.m. near Alcatraz Island while passengers were spreading the ashes of a loved one.

Rescuers and bystanders were able to pull 17 people from the water. However, 79-year-old Clifford Boisa later died from his injuries. The three missing passengers include Boisa's wife and sister, along with a family friend, according to Ralph Boisa, a relative who survived the incident.

A comprehensive search operation involving 11 Coast Guard boats and four aircraft scoured approximately 950 square nautical miles for 23 consecutive hours before the effort was suspended on Wednesday evening. "We have completely saturated the search area," stated U.S. Coast Guard Captain Jarod Toczko at a press conference. "Suspending a search is one of the hardest parts of our job and our condolences are with the families of all involved."

Captain Toczko also indicated a "high possibility" that the missing passengers were inside the three-level pleasure craft, named the Volare, when it was struck by a wave and subsequently capsized. Survivors reported the boat listing heavily before sinking to depths of up to 130 feet.

Survivors and authorities have said that the missing passengers may have been trapped inside the vessel's three-level cabin when the boat, called the Volare, sank

Officials are considering the recovery of the vessel, which could provide crucial information about the cause of the sinking and the fate of the missing passengers. However, the potential depth of the submerged craft presents significant challenges for recovery efforts. Diving operations beyond 120 feet in the busy shipping channel are considered dangerous and complex.

Ralph Boisa told the San Francisco Chronicle that at least four people were in the cabin when the Volare sank. He identified his other daughter, two aunts named Carol and Jackie Boisa, and a friend of his late daughter as being inside the cabin. He recounted that his daughter stated they struggled to escape, but she was the only one to get out while the others were pulled below.

A survivor of the accident said four people had been trapped in the boat when it sank, but his daughter was the only one to have escaped

The group on board the Volare were friends and family members gathered to spread the ashes of Maria Boisa, Ralph Boisa's daughter, who died by suicide in 2016. The passenger who died in the sinking, Clifford Boisa, was identified as the father of Maria.

The passenger killed on Tuesday was identified as Clifford Boisa, 79, (left). He was pulled from the water but succumbed to his injuries

Authorities have corroborated witness accounts of people being trapped inside the boat during its sinking. The Volare had departed from the vicinity of the St. Francis Yacht Club, traveled under the Golden Gate Bridge, visited Angel Island State Park, and was reportedly on its return trip when the incident occurred.

After the boat sank a huge search effort consisting of four aircraft and 11 boats was launched. One of the aircraft is pictured in front of the Golden Gate Bridge

No small craft advisories were in effect at the time of the sinking. Meteorologists from the National Weather Service indicated that conditions on the bay were typical, with winds around 17 mph. However, Lieutenant Joseph England of the Richmond Police Department noted that swells on the bay reached up to 5 feet that day, stating, "The wind was coming underneath the Golden Gate and blowing toward Alcatraz. If you have a smaller vessel and you don't know what you're doing and you're hitting those swells sideways, it can lead to disaster." The precise cause of the sinking remains under investigation.