American Witnesses Detail How Nice Festivities Turned Into 'Blood and Bodies Everywhere'

— -- Complete chaos. Hysterical screaming. Blood and bodies everywhere.

Those were among the words American eyewitnesses used to describe the Thursday night attack in Nice, France, during Bastille Day celebrations, after officials said a driver plowed into a crowd of over 30,000 people with a truck hauling grenades and other weapons.

Over 80 people were killed, including a man from Texas and his 11-year-old son, according to his relatives.

Before the carnage, "everything was normal," according to Mark Krikorian, a Washington, D.C., man who said he was in the area on vacation.

"I figured it was Bastille Day, I should go see the fireworks," Krikorian, executive director of the nonprofit Center for Immigration Studies, told ABC News.

"They were just like on the Fourth of July."

But a picturesque day of festivities turned into "complete chaos" in "literally split seconds," according to Inga Romanoff, a New York woman who said she was on the promenade when a truck drove into the crowd.

"It happened very quickly," Romanoff told ABC News. "We just heard the first gunshots. I started running, and I looked back and I saw the truck going through the people right in the place where I was standing."

People then began "running different directions," Romanoff said, but because "there was not enough space," many didn't have "any time to jump out of the way."

Krikorian added that he heard "hysterical screaming, running, people knocking tables over, glass shattering."

"And then the most grim thing I saw was a whole convoy of minivans from the Nice city coroner’s office arriving to do their work," he said.

Another U.S. citizen, Eric Drattell, said, "There were blood and bodies everywhere.”

This morning, a French teacher from New Jersey who witnessed the attack admitted he was "still a little shaky."

"I'm just trying to kind of move on," the teacher, Sam Helwani, told ABC News today.

Helwani, who has traveled to Nice for the past six years, said he didn't want to let what happened stop him from continuing his travels.

Krikorian added that he believed that "at this point, Nice is the safest place in all of France."

"You can't predict this kind of thing," he said. "It's going to happen, and you can't just put your life on hold just because of the possibility of this sort of thing. … You can't paralyze yourself because of it."