A transgender inmate was found dead in a jail cell on Rikers Island on Friday afternoon, law-enforcement sources told The Post.

The inmate was found unresponsive in her cell at the Rose M. Singer women’s facility at the notorious jail at about 2:40 p.m., the Department of Corrections said.

Medics responded and tried to revive her for about an hour before she was declared dead, the DOC said.

“Any death in our custody is a tragic loss, and we are looking into how this happened,” ‎a DOC spokesperson said.