An Ellicott City man faces assault charges after he fired glass marbles at a van carrying a speed camera, police said.

The operator of the van heard something strike the van about 5 p.m. Tuesday night, according to a Howard County police news release, then saw a man passing in a Chrysler minivan while firing a slingshot at the van.

The van operator called police, and officers stopped and arrested the minivan’s driver. Bruce L. May, 50, was charged with second-degree assault and other offenses, according to police.

Police said the incident was the third involving damage to a speed camera van this month. Someone threw an unknown object at a van near an Ellicott City elementary school, breaking its rear window, June 13, and someone threw rocks through the window of another van the day before, hitting the van’s operator.

Police say they are investigating whether the three incidents are connected.

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