A cracked windshield captured the interest of a state trooper patrolling in Brockton on Monday. A short time later, the car’s driver was arrested and authorities had seized $4,500 in cash and 450 grams of suspected heroin from a hideaway in the car.

Trooper Keith Ledlin was patrolling in the city south of Boston around 5:30 p.m. when he spotted the car, State Police said in a statement.

Ledlin pulled the car over and quickly shifted his focus from a traffic violation to potentially something more serious, especially after he allegedly saw the driver stuff something into his jacket, State Police said.

The driver was identified as Julio Monteiro, 26, of Brockton.

“Monteiro produced a Massa­chusetts driver’s license and a registration, but could not identify the owner of the ­vehicle,’’ State Police said.

Ledlin arrested Monteiro ­after learning his right to drive had been suspended, State ­Police said.

Searching Monteiro after taking him into custody, Ledlin allegedly discovered $4,500 in cash stuffed into one of ­Monteiro’s pockets, State Police said.

Ledlin called in a specially trained K-9 dog, and another discovery was allegedly made.

“The K-9 identified a hidden compartment in the vehicle; 450 grams of heroin were hidden inside the compartment,’’ State Police said.

Monteiro faces charges of heroin trafficking, operating with a suspended license, ­motor vehicle equipment violation, and failure to signal.

He was booked and held for his arraign­ment Tuesday morning in Brockton District Court.