"Green Mile” actor Michael Clarke Duncan remains on a hospital respirator after his heart attack Friday, but is showing signs of progress, according to a new report. The movie star has been sedated since his ICU arrival but is now “breathing above the respirator” in a sign he’s building strength, unidentified sources told TMZ.com. Duncan, 54, has a “very strong heartbeat” and “is fighting like a mutha,” the sources reportedly said.

Paramedics responded to a 911 call around 2 a.m. last Friday and rushed Duncan from his house in Woodland Hills, Calif., to a nearby hospital. Duncan's reality TV star girlfriend Omarosa Manigault-Stallworth found the ailing actor and performed CPR until medics arrived, possibly saving his life.