Photo: Alex Brandon/AP/Shutterstock

Mandatory Credit: Photo by Alex Brandon/AP/Shutterstock (13069803a) Washington Metro Police Lt. Jesse Porter speaks to the media, Dec. 11, 2013, in Washington. Porter, 58, and retired, was working for a private contractor providing training for a group of library police officers on how to use expandable batons when he discharged a single shot from his firearm, the Metropolitan Police Department said . The shooting happened around 3:30 p.m. Thursday inside a training room at the District of Columbia public library in the city’s Anacostia neighborhood Library Officer Shooting, Washington, United States - 11 Dec 2013

A retired police lieutenant allegedly shot a library officer dead during a training exercise at the Anacostia Neighborhood Library in Washington D.C. on Thursday.

The suspect — who was later identified as Jesse Porter, 58, a former police officer with the Metropolitan Police Department — was conducting ASP baton training with the library officers when the incident occurred, according to astatementfrom authorities on Friday.

The victim, police said, was 25-year-old Maurica Manyan of Indian Head, Maryland.

Upon arrival at the scene, at around 3:30 p.m. local time, members of the Metropolitan Police Department located Manyan suffering from a gunshot wound, per the police statement. DC Fire and Emergency Medical Services responded to the scene and transported the victim to an area hospital. Manyan was taken to a hospital and was pronounced dead soon after,The Washington Postreported.

The Metropolitan Police Department did not immediately respond to PEOPLE’s request for comment.

ASTRID RIECKEN For The Washington Post via Getty

WASHINGTON, D.C., JANUARY 20, 2011. The Anacostia Library is an environmentally-friendly building, using energy efficient lighting with a roof that reflects sunlight and keeps the building cooler in the summer. Solar panels on the roof are used to heat water for the building bio-retention pond that removes pollutants from rain water that flows into the Anacostia River. Low-flow faucets and toilets, and waterless urinals are used as well as automatic hand dryers in restrooms. The library was built with recycled materials in flooring, countertops and wood finishes. (Photo by ASTRID RIECKEN For The Washington Post via Getty Images)WASHINGTON, D.C., JANUARY 20, 2011. Benning Neighborhood Library provides community spaces, two 12-person conference rooms and a public gathering and exhibition space. The upper level of the library houses the librarys collection with about 40,000 books, DVDs, CDs and other library materials. Five small study rooms and 32 computers for public use are also provided. “Benning Library incorporates a vegetative green roof ( approximately 315 copper panels chosen for the exterior reflect the sun and provide a warm glow in the late afternoon), a displacement air system, solar control and daylight management and extensive use of recyclable and renewable materials. The quality and nature of light was an important factor in the design approach. The library is situated in a bowl-like condition with ample southern exposure.” (Photo by ASTRID RIECKEN For The Washington Post via Getty Images)

The documents also revealed that Manyan was the subject of some playful jokes about her hair and shoes, and she reportedly said she wanted to take off her mask. That was the moment when Porter pulled out his gun and fired, the documents said.

According to the police statement, which matches up with the affidavit, the instructor discharged a single round from a firearm that struck Manyan. A gun was recovered from the scene.

“I thought I had my training gun. Why did I do this? Is she ok?” Porter allegedly asked, per witness statements to police, NBC Washington reported.

A D.C. police officer who was at the scene said she saw Porter performing CPR on Manyan in an attempt to save her, according to thePost.

In a news conference from the Metropolitan Police Department, Chief of Police Robert J. Contee III could not explain why Porter carried a real gun with live ammunition. “I’m not certain why,” he told reporters. “I don’t have answers as to why the live firearm was in the ASP baton training.”

Porter was arrested and charged with involuntary manslaughter, the Metropolitan Police Department said in their release.

Upon his arrest, Porter turned to the arresting officer and reportedly said, “I’m sorry I shot your officer,” NBC Washington reported.

Witnesses also shared that Porter was carrying a brightly colored training gun — a replica — in his holster until the time of the shooting.

“There are props and firearm lookalikes that are in a training environment. They were present in this environment,” Chief of Police Contee III said. “But why and what kind of was in his mind at this time, I don’t know the answer to that.”

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Porter appeared in court Friday and was released from custody until trial. He was ordered not to possess any weapons and to turn over any personal firearms to police, per thePost.

source: people.com