The family of a mentally ill Colorado prison inmate who died while in restraints has filed a lawsuit alleging guards ignored his urgent medical needs.

A federal lawsuit filed Thursday says at least 16 state prison staff members did nothing to help as 35-year-old Christopher Lopez suffered a series of seizures and died at the San Carlos prison in March 2013.

The lawsuit says that when guards found Lopez unresponsive on his cell floor, they treated it as a behavioral problem instead of a medical emergency and put him in chains and shackles. The family says he had bipolar schizoaffective disorder.

The lawsuit says the incident was captured on prison cameras.

Department of Corrections spokeswoman Adrienne Jacobson says the agency doesn't condone the actions of employees involved. She confirmed three employees were fired and five were reprimanded.