DALLAS—About 500 people crowded Saturday into the plaza where John F. Kennedy was shot 45 years ago, all agreeing it was right to remember a pivotal moment in American history, even if they didn’t all believe the official line.

People stood shoulder to shoulder and bowed their heads during a moment of silence at 12:30 p.m. Some hawked JFK memorabilia or pitched conspiracy theories to visitors. Others offered firsthand accounts of their memories of the killing.

Visiting from Pipersville, Penn., 66-year-old Barbara Koenig said coming to the site was something she needed to do.

“I remember the day of the assassination, and I’ve always wanted to visit this site,” she said. “It’s just an eerie feeling. It kind of takes you back 45 years to what you were doing and thinking about the whole tragedy of the affair. I burst into tears (then). In fact, I’m ready to cry now.”

Nearby, street vendors held out commemorative newspapers hoping would-be customers would buy them. One person roamed the crowd with a sign questioning whether it was a lone gunman who killed Kennedy or several.

A group of men who wore black suits, matching ties and earpieces stood silent and appeared to guard a large black banner behind them.

The day Kennedy was assassinated is one people should always remember, but its truth still has not been entirely revealed, argued John Judge, head of the Coalition On Political Assassinations, a Washington-based organization that researches political assassinations.

Judge believes Kennedy’s assassination was a government conspiracy and could easily be solved if all of the facts were revealed.

“If the case were to be honestly investigated or if a grand jury could open it up, we could get at it,” he said. “I think (people) want to remember a piece of their history that was stolen from them.”

On Saturday, two Xs spray-painted in the street marked the spots where Kennedy was hit as his motorcade drove through the plaza. A placard from the National Park Service stood on the ground directly across from one X.

For 68-year-old Ann Murphy, news of Kennedy’s assassination stunned her when it reached her and other teachers in Toronto. She was in disbelief when school officials announced, “President Kennedy has been shot in Dallas,” she said.

Murphy stayed glued to her father’s grainy, black-and-white television set for more news on the events unfolding in the United States. She was even more stunned when she saw nightclub owner Jack Ruby later shoot the suspect in Kennedy’s assassination, Lee Harvey Oswald, on live television, Murphy said.

“It’s strange,” she said, “that one man’s influence and popularity would extend well outside his own country.”