A teenager has unknowingly filmed his mate’s last known moment alive after he was washed down a river by a strong current.

Raymond Cabalfin Jr was in high spirits as he and another friend jumped into the America River alongside Lake Clementine Trail in Sacramento last week.

While the young girl was able to quickly return to the riverbank, Cabalfin was quickly overwhelmed by the fast moving river and his laughs dissipate as he tries to escape the current.

His friends could also be heard laughing but when his attempts to swim to either side of the river failed, they realised the urgency of the situation.

View photos Raymond Cabalfin Jr was laughing with his friends before he jumped into the river. Source: Vimeo More

View photos The river is reportedly flowing at twice the normal strength. Source: Vimeo More

View photos Raymond quickly knew he was in trouble and called out for help. Source: Vimeo More

While the 19-year-old's parents have urged search parties to keep looking, Auburn State Recreation Area Superintendent Mike Howard was rather blunt about his chances of survival.

“It’s not likely that he is alive,” Mr Howard told reporters.

"We had enough … people search the area, and if he was alive, we would have found him."

Friends and family have started raising money on GoFundMe to help fund their own search efforts but park rangers have warned them to stay out of the water.