A disabled white man was attacked on a Maryland mass transit bus by an African American who seemed to be blaming the victim for putting his ancestors into slavery, according to police.

The 52-year-old victim was a passenger on a Metro bus in the Washington, DC, suburb of Silver Spring, Maryland, when Marquis Evans-Royster, 27, began spitting in his face and hurling racial epithets at him, according to ABC in Washington.

The harassment began almost immediately after Evans-Royster boarded the bus without paying the fare, police said.

The victim, who is homeless and remains unnamed in reports, initially tried to ignore Evans-Royster’s taunts but finally tried to push the attacker away when he began to go through the victim’s pockets while yelling, “You owe me for making my grandmother a slave.”

When other passengers began to try and intervene to stop Evans-Royster from attacking the victim, the attacker threatened to douse them with urine.

The threat caused one bus rider to tell the media that Evans-Royster must also have some sort of mental problem. “Who carries around a bottle a urine?” bus rider Desi Cureton scoffed.

At length, the bus driver threatened to call police causing Evans-Royster to jump off the bus and run away.

Police identified Evans-Royster from bus surveillance video and he was arrested four days after the incident and charged with assault and racial harassment. The attacker already has a long police record including charges of race or religious harassment, robbery, and assault.

Tyrone Kenney, a 70-year-old black man who grew up during the Civil Rights Era, decried the incident.

“It speaks to the state of the times,” Kenney said. “People are desperate, they’re looking for leadership, they’re looking for guidance, but they’re not getting it at home, they’re not getting it from government. It’s a period of time I’ve never seen before.”

Evans-Royster will be represented by a public defender and will next appear in court on October 27.

Follow Warner Todd Huston on Twitter @warnerthuston