BALTIMORE (WJZ) — It may be illegal to be a Tyrannosaurus Rex in Cecil County.

Twin brothers Mason and Connor Zack of Elkton found that out as they celebrated their sixth birthday on Sunday night, a tipster told WJZ.

The twins decided to use the T-Rex costumes they got for their birthday to greet passersby, but took off when a sheriff’s deputy pulled up.

Video uploaded to Facebook, which has been shared hundreds of times, shows the two mini dinosaurs leading the deputy on a low-speed chase down the street.

Said our tipster, “It really made them happy that the deputy played along with them.”