One person was hospitalized and two others were injured on Saturday when a boat caught fire in the middle of Lake Elsinore, according to the Riverside County Fire Department. 

The blaze was reported just before 6:30 p.m., and was confined to one vessel, firefighters said. 

Crews took one person to a nearby hospital with moderate injuries, while the two other people on the boat declined medical transport for minor injuries. 

Firefighters said that the flames were extinguished a little after 7:20 p.m. and that the vessel was then towed from the water. 

Both Cal Fire and the Riverside County Sheriff's Office were working to determine what caused the fire. 

On Sunday, CBS LA spoke with a good Samaritan who sprang into action to help the victims when they first got trapped on the burning vessel. 

"There's no thinking. We were like, 'There's people who are in trouble, a boat's on fire; let's roll,'" said Kenneth Kwak, who was at his lake house on Saturday when they saw the fire break out. 

He says that he and some of his friends jumped onto his boat and reached the group of people just as the flames forced them to jump into the water. 

"It was a pretty big fire and it was pretty hot," he said. "I could feel the heat coming off, radiating. I was like, 'Jump in and let's go.'"

Kwak said the moment was full circle for him after he was rescued from his own boat that caught fire in the middle of the ocean more than three decades ago. 

"I was the one on the other side," he said. "I'm glad I was able to help somebody and pay it forward."