A police sergeant has been indicted on charges he chased another officer on a highway at high speed before pulling a gun on him during a roadside encounter.

Sgt. Teddy Cerra, of the Franklin Township police in Somerset County, is charged with second-degree possession of a weapon for an unlawful purpose, and two counts of aggravated assault: one third-degree and the other fourth-degree. Burlington County Prosecutor Scott Coffina announced the indictment, dated Sept. 20, in a news statement Tuesday.

Cerra, a 43-year-old Southampton resident, is suspended without pay from the department after the Nov. 1 incident last year.

That all started, Coffina said, when an off-duty Lumberton police officer was driving his personal car in Southampton.

That officer noticed Cerra driving "in an erratic manner," notified police dispatch and tailed Cerra in his car. The two stopped on the shoulder of Red Lion Road, where Cerra got out of his car, pulled a gun and pointed it at the Lumberton officer, Coffina said.

Prosecutors said at a detention hearing that Cerra told the Lumberton officer about his law enforcment status, saying "I'm blue."

"I'm blue, too," the Lumberton officer said, getting on the ground when he saw Cerra's gun.

He showed Cerra his police ID before getting back in his car and driving away. This time, Cerra was chasing him. At the detention hearing, prosecutors said the vehicles broke 100 mph in parts of the chase.

The chase ended when Cerra struck a vehicle and mailbox. New Jersey State Police apprehended him and took the gun from his waistband.

Cerra also received summonses for reckless driving and operating a motor vehicle under the influence of liquor or drugs.

Joe Brandt can be reached at jbrandt@njadvancemedia.com. Follow him on Twitter @JBrandt_NJ. Find NJ.com on Facebook.

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