Caped crusader: Leonard B. Robinson in 2012. Photo / Washington Post / Jonathan Newton

The Maryland Batman, whose roadside encounter with police three years ago made him a viral sensation around the world, has died.

Lenny B. Robinson, the 51-year-old Maryland man who drove a custom-made Batmobile and dressed as the Caped Crusader to visit sick children in hospitals, was struck by a car on Interstate 70 Sunday night near Hagerstown, Maryland, after the Batmobile broke down. He was coming home from a car show in West Virginia.

Robinson had just stopped at a gas station, where he met a family whose children were interested in his custom-made car, Maryland state police in Hagerstown said. Robinson gave the kids some superhero paraphernalia before leaving about the same time as his new acquaintances. When they saw him pull over, they did the same and witnessed the 10:30 p.m. accident, state police said.

Robinson was having engine trouble and stopped "partially in the fast lane," according to a state police news release. He was checking the engine when the Batmobile was struck by a Toyota Camry. The Batmobile then hit him. Robinson was pronounced dead at the scene.

The crash is still under investigation, and no charges have been filed. The driver of the car, who wasn't injured, declined to comment.

The Post revealed Batman's identity to the world in 2012, after Robinson was pulled over in Silver Spring, Maryland, in his Lamborghini and full superhero costume. Video of his encounter with police, who had pulled him over because of a problem with his plates, emblazoned with the Batman symbol, made him an instant sensation on the Web.

The Dark Knight's encounter with law enforcement began turning up in millions of Facebook news feeds. The episode even made it into a Jimmy Fallon monologue.

Robinson, who lived outside of Baltimore, had cleaned up in the cleaning business, making enough money to buy his own Batmobile, a costume that seemed more real than the one in the movies, and toys and memorabilia that he handed out to children with cancer at hospitals all over Maryland and the District.

On one visit to Children's National Medical Center in Washington, Batman reflected on the health of his own three children. "We're lucky," he said.

At Children's Hospital, there were kids with tubes in their noses, with IVs in their arms. Batman handed out gifts: books, rubber symbol bracelets and other toys.

Batman made those kids smile. They all thought he was Batman, a hero.

"I'm just doing it for the kids," he said.

Robinson worked closely with Hope for Henry, a Washington organization that helps sick children. Founded by Laurie Strongin and Allen Goldberg after their son Henry died from a rare disease, the group threw superhero parties in hospitals. Batman was always the star.

"He made so many kids so happy," Strongin said. "When I asked him to do anything, he always said yes."

Robinson had never met Henry.

"But he called me every year on his birthday," Strongin said.

Strongin has been crying all morning. The organization had just finished producing a video about the program. It starts with a little boy dressed as Batman. He has leukemia. He's waiting outside a hospital. The real Batman - Lenny Robinson - pulls up in his Batmobile, gets out and hugs the boy.

"He was magic," Strongin said.