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FRISCO (CBSDFW.COM) – Officials with the city of Frisco said they can’t explain a significant increase in red-light camera tickets there in the past year.

Compared to a year ago, the number of drivers caught by the city’s four red-light cameras is up 59 percent, according to police records.

The city’s four cameras cover three high-volume intersections – Preston and Lebanon, Preston and Gaylord, and Legacy and Main.

Police Chief John Bruce pointed out the 59 percent increase in red-light camera summons to city council Tuesday night, but when asked Wednesday to explain the increase, the department couldn’t.

No new cameras were added in the past year; there are still just four.

The city said traffic volume along Preston has not seen a significant change in the past year, while traffic at Main and Legacy has increased but not nearly enough to explain a 59 percent increase in tickets.

On Wednesday, a red-light camera at Preston and Lebanon caught Andrew Humstiger crossing the intersection on red.

“I’ve been through there a couple of dozen times, but this time it (the yellow light) seemed shorter than normal,” said Humstiger.

The city’s traffic light department also said the timing of the yellow and red lights at the intersections have not changed in the past year.

So why then the increase in red-light camera violators? No one seems to know.

Members of Frisco’s red-light citizens committee said they are aware of the increase and are working to pin-point an explanation.

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