SAN DIEGO — The case of a detained college student who was forgotten in a holding cell for more than four days suggests a breakdown in procedure and oversight within the Drug Enforcement Administration, a California federal lawmaker said Thursday.

Republican Congressman Duncan Hunter said in a letter sent Thursday to DEA Administrator Michele Leonhart that the treatment of 23-year-old Daniel Chong raises concerns about the agency’s handling and monitoring of individuals in custody.

Chong was swept up in a drug raid on April 21. After questioning him, agents told him that he would not be charged and to hang tight in the holding cell until they finished the paperwork to release him.

The door did not reopen until April 25 when agents found a severely dehydrated Chong covered in his own feces. Chong spent five days in the hospital.

The incident was one of the worst cases of its kind, law enforcement experts say.

Hunter said he wants a full account of Chong’s incarceration, the process currently in place for holding individuals suspected of unlawful activity and the steps that the DEA is taking to address this matter in its entirety.