A gunman shot and wounded a police officer and two employees at a Birmingham, Ala., hospital early Saturday before being shot to death by another officer, authorities said.

The shooting happened shortly after 4 a.m. on the fifth floor of at St. Vincent’s Hospital, WVTM-TV and al.com  reported.

Two officers responding to a report of an armed man inside the facility entered the floor from different locations.

"When the officer encountered the suspect, there was immediate gunfire from the suspect," Birmingham Police Sgt. Johnny Williams said, according to The Associated Press.

One officer and two hospital workers were wounded. 

A second officer shot and killed the suspect.

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The injuries to the officer and employees were not life-threatening, Williams said, according to al.com.

Detectives were trying to determine why the armed man was in the hospital. Authorities did not immediately release the names of the suspect or the victims.

The Associated Press contributed to this report.

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Carol Robinson / al.com

Birmingham police on Thursday arrested a costumed woman on a DUI charge after responding to a report that she was shot. A passerby called 911 after seeing the woman unresponsive at a traffic light.

Updated at 6:57 p.m. ET: Birmingham, Ala., police got a Halloween surprise when they responded to a concerned citizen’s 911 call of a woman shot in her SUV at a city intersection.

Officers found a woman bloodied and slumped over the wheel of her car at a traffic light Thursday morning, al.com reports.

But the blood wasn’t real, and she hadn’t been shot. Instead, police told al.com, she was just drunk and still dressed in her Halloween costume, which appeared to resemble something like a blood-splattered, pregnant zombie.

"We’re unsure the amount of time she was at the intersection, but we do know that it was not a very long period of time, due to the location. It’s a busy intersection and it would be easy to cause a delay in traffic," police Sgt. Johnny Williams told NBC News via email.  

"I can say that we are uncertain what her costume represented, but it did entail face paint and a large amount of fake blood. She believed that officers pulled her over, but they had to wake her as she sat at a traffic signal. The car was still running (in gear) when officers managed to wake her. "

The woman was taken to the city jail on a DUI charge, al.com reported.

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