A Brooklyn family has sued the Metropolitan Transit Authority after they said a bus driver called their 10-year-old son a “terrorist” and prevented him from boarding a bus.

The boy said he began reciting a Muslim prayer in Arabic because he couldn’t find his bus pass one afternoon in October 2012.

“I start in the name of God, the most merciful, the most beneficent,” the boy said, according to the suit.

The prayer is commonly used by Muslims in the face of a challenge, and the boy said it must have worked, because he found his card and began to board the B-39 bus in Sheepshead Bay.

But the driver accused him of being a terrorist and forced the boy off the bus before closing the doors, according to the suit.

The boy told his parents what had happened after he got home, and they met with representatives from the MTA.

The transit authorities showed the family photos of various drivers to help identify him, but they said they were never told who he was.

The suit claims religious discrimination and civil-rights damages, and the family is seeking unspecified damages from the agency and the driver.

The MTA declined comment.

[Screaming bus driver via Shutterstock]