The hate crime in the guise of a terrorist attack in Orlando, Fla., early Sunday has put the national and worldwide lesbian, gay, bisexual and transgender community on high alert, the director of the Denver-based Matthew Shepard Foundation said.

The LGBT community has made great strides in recent decades from gathering in exclusive groups to gaining acceptance within the larger American society, Jason Marsden said.

But the attack in the Pulse nightclub that left 50 people dead including gunman Omar Mateen, and wounded 53 others has re-awakened the fears that have plagued the LGBT community for years, said Marsden, a Wyoming native and former Casper resident.

"The real impact of this case is that gay and lesbian and transgender Americans all across the country, and frankly in other countries, suddenly now have a great deal of additional reason to be afraid to be in their own communities' safe space," he said.

Those safe spaces included nightclubs and community centers, Marsden said. "(They are) places that the LGBT (community) created for themselves over the past 40 years in order to be safe from prejudice, and from gay-bashing, and from murders and other terrible tragedies like that."

The Matthew Shepard Foundation was founded by the parents of the Casper native who was a University of Wyoming student when he was murdered Laramie in October 1998. Marsden, a former Casper Star-Tribune reporter, now heads the group with the mission to empower people "to embrace human dignity and diversity through outreach, advocacy and resource programs...."

While the investigation continues, Mateen's actions appear as a hate crime in the guise of a terrorist act, Marsden said.

Mateen called 911 before the attack and pledged allegiance to the fundamentalist Sunni Muslim terrorist organization ISIS, which is trying to establish a modern caliphate in Syria and Iraq.

The seriousness of a tie to ISIS remains under investigation.

"I've come to call it 'hashtag terrorism,' where someone wants to go out and has a grudge against some community, against some organization or their workplace and now they can, after the fact, claim it as an act of international terrorism as well as whatever other crime it happened to be," Marsden said.

Mateen apparently had mental health issues and had become radicalized in recent years, but his father said he also had strong anti-gay attitudes, Marsden said.

"It's pretty clear that he shot up a gay nightclub on purpose," he said. "That's the definition of a hate crime."

Hate crimes traditionally have been defined as acts that send fear to an entire community whose members are similar to those of the victim, Marsden said. "It starts with Ku Klux Klan cross burnings and ends with what happened after midnight Sunday morning in Orlando."

Even so, Marsden said those in the LGBT community should resist the urge to withdraw from society at large.

"The most important thing everyone can do now is to resolve to continue to be their authentic selves day in and day out, and not to be intimidated by the prospect of unspeakable violence coming from out of nowhere," he said.