The lead detective in the infamous Jeffrey Dahmer case is issuing a warning to a psychiatric review board that granted conditional release to a Connecticut cannibal killer — Don’t let him out!

Retired Milwaukee detective Dennis Murphy — who took Dahmer’s 1991 confession in which he discussed eating a human heart, bicep and thigh — says Bridgeport, CT, killer cannibal Tyree Smith should stay locked away at a maximum-security forensic hospital.

Murphy says after Dahmer was convicted for his serial murders in 1992 and sentenced to multiple life terms, the detective went to visit him in a Wisconsin prison.

This is why Murphy says Smith should never see the light of day … because he would just revert back to his sick, twisted ways like Dahmer. Murphy also says Smith’s release from the hospital would negatively impact the victim’s family.

In 2011, Smith hacked Angel Gonzalez to death in Bridgeport and later confessed to his cousin he ate a portion of Gonzalez’s brain and an eyeball, washing it all down with sake. The following year, Smith was found not guilty by reason of insanity and ordered confined to the psychiatric hospital for 60 years.

But, last Friday, the Connecticut Psychiatric Security Review Board granted Smith conditional release from the mental ward after a psychiatrist evaluated Smith and concluded his schizophrenia was in full remission along with his alcohol and drug issues as a result of his ongoing treatment, which includes taking meds.

Murphy says mentally unstable inmates often stop taking their meds for any number of reasons, potentially triggering a violent episode.

The review board’s decision means Smith will be released from the high-security forensic hospital and housed full-time at a community facility with 24/7 supervision.