A D.C. Department of Transportation crossing guard stabbed a MetroAccess driver during an argument Wednesday morning, police said.

Reginald Wilson, 31, was working at a crosswalk in the 100 block of T Street SE near Langley Elementary School when the MetroAccess bus driver stopped in the crosswalk to pick up senior citizens, police said.

Wilson got into an argument with the driver, who got out of the bus, police said.

Wilson pulled out a knife and stabbed the driver, police said.

The victim was taken to a hospital.

Wilson was arrested and charged with assault with a dangerous weapon.

Witnesses told police they saw Wilson approach the victim with a knife in his hand, and Wilson admitted he cut the victim, police said.

“I think it’s concerning,” D.C. police Cmdr. William Fitzgerald said. “It just shows people’s carefreeness. You’re entrusted with responsibility for children, getting children to and from the school safely and you’re carrying a knife yourself. I don’t know how we can enforce that. We can’t be patting down every crossing guard that’s on the street, but maybe the character of people being hired needs to be questioned.”

Children were never in danger, Fitzgerald said.