Former “Biggest Loser” contender Sam Poueu found himself  locked out on a San Francisco  building rooftop during a party and fell several stories when he tried to climb down a fire escape, his family and his fiancee’s family told People magazine.

In an exclusive statement to People magazine, the families explained that following a friend’s birthday dinner, Sam  went to the rooftop of a friend’s apartment building and later found that the door to the rooftop had locked behind him.

Poueu then “attempted to climb down the fire escape ladder to drop down into the fourth-floor balcony and slipped,” they told People, adding that the San Francisco Fire Department responded within minutes of a neighbor’s immediate call.

Fan favorite Poueu, 25, also “suffered many serious internal injuries and a trauma to the right side of his head,” their statement continued. ”Sam has made positive and encouraging strides since his accident. Since being admitted to the hospital, Sam  has stayed strong through three surgeries. To date, many of his internal injuries are on the healing mend.”

Poueu is undergoing treatment for a pelvic injury, torn ligaments, a punctured lung and a broken leg sustained from the Sept. 3 fall, according to a TMZ report.

 ”Sam Poueu is a beloved member of our “Biggest Family,”  and we are keeping him and his family in our thoughts and prayers,” a rep from the NBC show said in a statement to People.

Fellow season-nine contestant Ashley Johnston has also been regularly updating “Biggest Loser” fans on her castmate’s condition via Facebook.

“Headed to see our boy Sam Poueu and tell him all about all the ppl that are praying for him, making bracelets, raising money, and just simply showing that there are still amazing ppl in the world! XOXOXO,” Johnston posted Monday.

Facebook  fans are selling wristband bracelets to support Poueu’s recovery.

Poueu’s fiancee Stephanie Anderson also posted a note on Facebook about a trust fund to help pay for Poueu’s medical expenses. The couple first met at the “Biggest Loser” ranch in 2009.

Poueu, a former security guard, entered “Biggest Loser” as a “Grey Team” contestant weighing  372 pounds, losing more than 100 pounds before the season’s end.  At the time of his accident, he had been working as a physical trainer at the Biggest Loser Resort at Fitness Ridge in Malibu, the resort of the weight-loss reality show. Poueu and Anderson currently do not have any plans to pursue reality television, Cynthia Wang, assistant editor at People magazine, told ABCNews.com.

“Biggest Loser” is currently in its 12th season on NBC, and has spawned a variety of video games, books and workout regimens. The show has also boosted the profile of several athletic trainers and personalities who have appeared on the show, including Jillian Michaels, Bob Harper and Ali Sweeney.