Update 5:25 p.m. ET: Law enforcement sources told NBC News that the shooter is a woman and she is down, a tweet from the news outlet confirms.

BREAKING: YouTube shooter is a female and she is down, multiple law enforcement sources tell @NBCNews - @anblanxhttps://t.co/YQ0x5rJFwo — NBC News (@NBCNews) April 3, 2018

ORIGINAL: Following reports of an active shooter at YouTube headquarters, one employee claimed that he believed the shooter is female.

In a series of text messages sent to a friend, an employee at the YouTube headquarters in San Bruno, California, alleges that the reported active shooter is female.

(Photo: Twitter / @MrWillToLive)

In the string of text messages, the employee goes on to claim that he received the information through a group chat with coworkers and that “a lot of people are still inside on lockdown” as the shooter had not been found yet.

The text messages were first posted to Twitter but have since been deleted. Authorities have not yet commented on whether the possible shooter is male or female.

The reports of an active shooter on campus at YouTube's offices came mid-afternoon on Tuesday when employees began tweeting about the possibility and friends and family began sharing text message screenshots from other employees who are on the scene.

Employees reported heard gunshots and quickly began to barricade themselves inside, according to CBS News.

The City Manager confirmed to local news stations that they had received multiple 911 calls from YouTube but did not immediately disclose the reason for the calls.

The San Mateo County Sheriff's Office has confirmed that they are treating the situation as an "active shooter incident," but they did not confirm that they have eyes on an active shooter.

CBS News added during a broadcast that they have received reports of shooting victims being taken to the hospital to be treated for injuries, but a reporter on the scene explained that he has not seen anyone taken away in an ambulance.

The San Bruno Police Department reportedly claimed via police scanner that 37 people have been injured inside the building.

“37 at the hospital” says San Bruno PD scanner — paris martineau (@parismartineau) April 3, 2018

San Francisco General Hospital also confirmed that they were receiving patients from the shooting, though they declined to reveal how many.