What we know about the NYC shooting and suspect Shane Devon Temura

A gunman opened fire inside a high-rise corporate building in the heart of Manhattan on Monday evening, killing a New York City police officer and four others, officials said.

The suspected shooter acted alone and died from a self-inflicted gunshot wound, law enforcement officials told NBC News.

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The deadly gunfire, which was first reported about 6:30 p.m., was treated as an active shooting, prompting warnings and office evacuations, with lines of people seen leaving the building with their hands above their heads.

The gunman’s motive for the shooting has not been disclosed.

Here’s what we know so far:

The victims

A New York City police officer was killed in the shooting, three senior law enforcement officials said.

The officer’s family has been notified of the death, but their identity has not been made public.

Four civilians also died in the incident. Their names have not been released.

The gunman

Law enforcement officials said the violence was carried out by a lone gunman, who died from a self-inflicted gunshot wound.

The suspected shooter has been identified as Shane Devon Tamura, 27, of Las Vegas, according to four senior law enforcement officials.

In a photo three law enforcement officials shared with NBC News, the suspected gunman was seen walking into the midtown Manhattan building wearing dark clothes and sunglasses and carrying what appeared to be a large firearm.

A motive in the shooting has not been determined.

The building

Midtown Manhattan’s 345 Park Ave. is the headquarters of the investment firm Blackstone.

The building also hosts the headquarters of the NFL and a Bank of America branch, as well as offices belonging to KPMG.

Blackstone, Bank of America and the building’s owner, Rudin Management, did not immediately respond to requests for comment about Monday night’s shooting.

In a statement, KPMG said its thoughts were with victims and their families.

“Our hearts go out to the victims of this horrific act and their families,” the company said. “We are incredibly grateful for the bravery of building security and law enforcement.”