San Quentin investigating homicide of 66-year-old inmate
![](https://images.foxtv.com/static.ktvu.com/www.ktvu.com/content/uploads/2020/12/764/432/SAN-QUENTIN.jpeg?ve=1&tl=1)
SAN QUENTIN, Calif. - San Quentin State Prison officials on Wednesday say are investigating the death of inmate 66-year-old man as a homicide.
In a statement, the prison said that just before 1 a.m. a correctional officer found John Sullivan unresponsive in his cell while conducting an institution population count.
Despite life-saving measures, Sullivan was pronounced dead at 1:18 a.m.
![](https://images.foxtv.com/static.ktvu.com/www.ktvu.com/content/uploads/2021/03/932/524/San-Q.jpg?ve=1&tl=1)
San Quentin officials said that Sullivan had been sent there on March 3, 2016, from Placer County to serve a 10-year sentence for failure to register as a sex offender, a second-strike.
Investigators identified Sammeon Waller, 28, as the suspect.
Officials did not provide evidence to back up that accusation or provide a possible motive. They also did not say how Sullivan died.
Waller was admitted from Los Angeles County on Dec. 20, 2017, to serve seven years for first-degree burglary and injury to a dependent adult causing deathor great bodily injury.
He has been rehoused in the Administrative Segregation Unit pending the investigation.
![](https://images.foxtv.com/static.ktvu.com/www.ktvu.com/content/uploads/2021/03/932/524/Sullivan-John-AZ2409.jpg?ve=1&tl=1)
John Sullivan was killed on March 10, 2021
![](https://images.foxtv.com/static.ktvu.com/www.ktvu.com/content/uploads/2021/03/932/524/Waller-Sammeon-BF0503.jpg?ve=1&tl=1)
Sammeon Waller is accused of killing inmate John Sullivan on March 10, 2021