The body of San Francisco 49ers fan Ian Powers, who went missing following the team's game at Levi's Stadium last week, was found in the waters of the San Francisco Bay Saturday, about a mile from Alviso Marina, according to a family member.

Authorities confirmed Powers' death Tuesday morning, stating that the cause of the 32-year-old man's death was salt water drowning. Police speculate that Powers, who did not know how to swim, somehow ended up in the Guadalupe River near the stadium before his body was found days later.

"The manner of death has been ruled an accident," according to a statement released by police. "Based on these findings, the Santa Clara Police Department’s investigation into Powers' disappearance is now closed."

Powers, a resident of Spokane, Washington, was last seen at the Nov. 12 NFL game between the 49ers and New York Giants at Levi's Stadium, where he left his seat late in the game and went to the restroom. His disappearance set off a massive search involving multiple agencies and family members.

via Santa Clara PD

Days after the disappearance, Santa Clara police released surveillance video showing Powers walking out of Levi's Stadium, appearing to be looking at his cellphone. He was reportedly on his phone with his girlfriend, Chelsea Robbins, trying to figure out how to get back to their car, but his phone eventually died.

Police said Powers had been drinking and probably became disoriented. His girlfriend was waiting at their car blocks away. But he never made it to their car.

Powers' girlfriend and her children — who were with him during the course of the game — waited by the car in the parking lot for hours afterward and ended up taking a bus back to their hotel in Concord. They were supposed to leave for Los Angeles the day after the game.

Police said they hadn't found any signs of foul play. They speculated Tuesday that Powers somehow ended up in the Guadalupe River, became stuck and eventually drowned. His body would have then traveled toward the Alviso Marina area.

"It's not easy to get into the waterway," Santa Clara Police Capt. Wahid Kazem said. "We can speculate to say maybe he thought that he could cross the waterway. Perhaps he thought that where he needed to be or his car or his family was on the other side of the waterway. I can understand where some may look at that waterway and think that, 'Oh, I can just run across this.' But if you actually step into the middle of that waterway, it's going to sink down quite a bit to the point where you're going to realize this is not as easy as I thought."

On Saturday afternoon, San Jose officers responded to reports of a body in the bay near the marina, police said. Rescue divers from the Santa Clara County Sheriff’s Office Dive Team assisted the coroner’s office in recovering the body and then handed it over to the coroner.

Police and the Santa Clara County Coroner's Office had not yet identified the body Monday when Powers' uncle confirmed the death in a social media post.

Hotstart, the Spokane company where Powers worked, released a statement Monday based on what it learned from the family member:

"Today is a very sad day for the Hotstart family as we learned the news of Ian Powers. Our hearts are very heavy as we grieve. It is hard to imagine not having him here. He was very friendly, talented, dependable and fun to be around. We will miss him very much. Our hearts go out to his family, friends and others he touched."