COLUMBUS, Ga. (AP) - Authorities have released the names of two people who were shot and killed at a west Georgia hospital by a man who apparently carried a grudge against his late mother's treatment at the hospital.

Columbus Police Chief Ricky Boren says the two were a nurse, 44-year-old nurse Peter Wright of Fortson, and 76-year-old James David Baker of Columbus. He says Wright was shot inside Doctors Hospital and Baker was killed outside.

Authorities are withholding the identity of the third person, a 44-year-old administrative assistant, until they can notify his relatives.

Authorities plan to charge 63-year-old Charles Johnston with three counts of murder when he is released from the hospital where he's being treated after he was shot by a detective in the hospital parking lot.

Johnston is listed in "guarded" condition at The Medical Center In Columbus.

Boren says he also will be charged with four counts of aggravated assault on a police officer and aggravated assault on a civilian.

The director of communications for Muscogee County Schools, Valerie Fuller, says Johnston was a teacher's aide from September 1973 to December 1973 at Rothschild Junior High School. She says he resigned in 1973 for personal reasons.

Fuller says in 1997, he enrolled in a class to train substitute teachers. May 2007 is the last time the system has him on the payroll as a substitute.

Johnston lived not far from the hospital where the shootings occurred.

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