An eagle-eyed witness helped police bust a suspected Beacon Hill smash-and-grab suspect late last night who was caught with a brick in his hand.

Police reports tell how first “a caller inside” a Charles Street address saw a suspect “kick the window of the business across the street” and take off running. Police dispatched to the area quickly came upon a robbery in progress.

“The alarm company (was) reporting … a person inside by the cash registers” at a jewelry store on the street, police report.

More officers were called in for back-up where they reported finding bricks on the street at the scene of the first broken glass and again the same brick-and-broken-glass destruction at the Tibet Emporium on Charles Street.

Police noted the area has been hit by thieves last summer and they intensified their search.

The report states $1,500 in cash, iPads, $700 in bills, and possibly more missing. They then kept on searching spotting a Charles Street door “slightly cracked open with light appearing” at around 11:36 p.m.

“While approaching the door, officers heard a ‘thump’ sound inside” and that’s when police report they drew their weapons with one officer using his foot to push open a door spotting a “white male suspect, wearing a black jacket, blue jeans, and green sneakers.”

He also had a telltale brick in his hand.

The suspect dropped the brick and was quickly handcuffed, the report ends. The suspect was identified as James Schaff, who will be arraigned sometime today.

At booking, police added, Schaff had “several jewelry items which were located in his black jacket.”

He was charged with breaking and entering in the night, destruction of property, and being a common thief.

This is a developing story …