Police have swarmed Las Vegas’ Boulevard Mall after reports of a possible active shooter.

Ambulances, and police vehicles were seen blaring their sirens and surrounding the building as armed officers reportedly guarded the entrance to Sears.

Social media users have claimed a masked man holding a gun is at the shopping mall north of Buffalo.

Police have not confirmed the reports, but parts of the mall are on lockdown and the parking lot is being cleared out, KTNV reported.

Nearby streets are also being locked down by police, and all entrances to the mall are being closed.

Dozens of armed officers raced to Boulevard Mall following reports a man armed with a shotgun entered the building.

Officers were seen preparing to breach the shopping centre’s doors as horrified bystanders watched on.

One witness said he saw a gunman, armed with a shotgun and wearing a mask.

Another said two people were down, but did not clarify whether they had been injured or killed.

This story is developing.

At least 10 units just zoomed by on Maryland Parkway rolling code. No one I’ve spoken to so far on the other side of the crime tape was inside Boulevard Mall when it was evacuated. pic.twitter.com/hkcR9MblVt — Rio Lacanlale (@riolacanlale) May 18, 2018

My twin sister says she was just escorted out of Boulevard Mall at gunpoint and that she was among the last to leave. She heard shots fired, says the shooter hasn't yet been apprehended. — Jennifer Wise (@sentenceswords) May 18, 2018

#BREAKING: There is a reported #ActiveShooter at the Blvd. Mall near Desert Inn & Maryland Pkwy. A sneaker store owner says there is a shooter right now. 2 possibly down. @KTNV — Joe Bartels (@Joe_Bartels) May 18, 2018

the scene outside Boulevard Mall right now pic.twitter.com/nmfewIVaXV — Bear Trills™ (@bigbadOSO) May 18, 2018

#BREAKING We are outside of the Boulevard Mall in Las Vegas. The parking lot is being cleared. Parts of mall on lockdown. @KTNV pic.twitter.com/UlgN6uMyLe — Mahsa Saeidi, Esq. (@MahsaWho) May 18, 2018

I think there was 2 males with shotguns or rifles and I heard from a worker at the mall that got out later than I did that they cornered the man or men into the food court and that’s all I know I got ou him of the mall before it got bad — Daeee ➡ EDCLV18 ✨ (@iam_dae) May 18, 2018

Just saw a dude with a mask and shotgun at boulevard mall be safe y’all — mza (@mario_urameshi) May 18, 2018

My friend is saying he’s on lockdown at the Las Vegas Boulevard Mall because of an active shooter. Less than 5 minutes ago. #BoulevardMall #activeshooter #ENOUGH — Claw K. (@ClawK11) May 18, 2018

There was legit hundreds of cops outside of this mall in Vegas holy shit it’s insane — Jimdalf (@Gymdalf) May 18, 2018

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