Backstreet Boys star Brian Littrell is wary every time he and his band perform in Las Vegas after last year's (17) Route 91 Harvest Festival massacre.

Almost 60 people were killed when a gunman opened fire on the crowd from his hotel room at the Mandalay Bay resort as Jason Aldean performed at the open-air event in October, and the singer admits he's now always on high alert when he's in Sin City, where the boy band is currently in the middle of a residency at the Planet Hollywood Resort & Casino.

"I was just in Vegas two weeks ago; we were performing," Brian tells TMZ, "and I was looking at all the hotels, all the windows, and it (massacre) crossed my mind. You just don't forget about it."

Littrell also had some harsh words for punk band NOFX, who made light of the tragedy during a recent gig in Las Vegas, joking, "I guess you only get shot in Vegas if you're in a country band," during a set at the Punk Rock Bowling & Music Festival on Sunday (27May18).

Brian is upset about the comment, insisting it was nothing but a tasteless publicity grab.

"Fans are fans...," he rages. "You don't joke about that... I mean people lost their lives...

"That's just somebody who needs press, so they run their mouths."

NOFX guitarist Eric Melvin's ill-advised remarks have cost the band their deal with bosses at Stone Brewing Co., the brewery which backs NOFX's Punk in Drublic beer and music festivals.

The company executives announced they were cutting all ties with the band on Wednesday (30May18).

"We at Stone Brewing are aware of NOFX's insensitive and indefensible statements this past weekend," a company spokesperson told The Blast. "As a result, we are severing all our ties with NOFX, including festival sponsorship and the production of our collaboration beer.

"We respect punk rock, and the DIY ethos for which it stands. To us, it means standing up for things you believe in, and fearlessly committing to what's right. And it is for that reason that Stone Brewing is immediately disassociating ourselves from the band NOFX."

The punk band has since apologised, releasing a statement on Thursday (31May18).

"I can’t sleep, no one in my band can. What we said in Vegas was sh**ty and insensitive and we are all embarrassed by our remarks," NOFX frontman 'Fat Mike' Burkett says, revealing he and his bandmates will be releasing an "in-depth, sincere and honest apology".