Chicago (CBS) — The healing process continues following last month’s deadly shootings at Mercy Hospital. A prayer service Saturday honored the lives lost.

Mercy Hospital workers and Chicago police officers attended the event, which remembered the lives of Dr. Tamara O’Neal, Dr. Dayna Less and CPD Officer Samuel Jimenez.

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Back on Nov. 19 in the hours following the chaos of a gunman’s domestic wrath, Mercy Hospital’s patients and workers faced a crisis, an evacuation, shock and eventually the grief of losing three innocent lives in the process, including a Chicago police officer.

Dr. Phillip Ahn looked forward to the ceremony so many could breathe, heal and then go on.

“Security had to improve and it has,” Ahn said. “It’s pretty much back to normal in terms of what were doing for our patients.”

Last month administrators told CBS 2 they will monitoring staff for PTSD, which can include anxiety and depression.