A California university student who was left in a holding cell for nearly five days without food or water said he drank his own urine to survive.

Daniel Chong, a 23-year-old student at the University of California San Diego, was accidentally left in a Drug Enforcement Agency holding cell for 4 1/2 days, NBC San Diego reported.

Chong told the station he was at a friend's house celebrating 4/20 - a day marijuana enthusiasts devote to getting high - when an agent came in and raided the place.

He said he was questioned at the DEA facility and then told he could go home - even offered a ride. But instead he says he was left in a cell for nearly five days without any contact and without food or drink.

He told NBC he was forced to drink his own urine to survive.

He said he tried to make noise to alert people in the facility of his presence in the cell, but his cries went unanswered until the fifth day.

"That was when I really felt my life go and for some reason they heard me that time and turned on the light and found me," he told NBC. "At first I was just relieved to be alive, 100%. I started realizing what happened to me. They told me I was in kidney failure, but for me, I just, I couldn't focus my eyes. I was pretty incoherent at the time, too."

The DEA said in a statement that Chong was detained after an ecstasy raid at a house in University City on April 21, NBC reported.

In the cell, Chong found a white powdery substance that he took, his lawyer confirmed. Testing revealed the substance to be meth.