Weymouth Police Officer Michael Chesna killed on Sunday morning leave behind two young children. Mike Saccone/Twitter

Officer Michael Chesna, a father of two, was shot and killed with his own gun while attending a call about a car accident.

A police officer and a 77-year-old woman were shot and killed in Massachusetts early Sunday morning after a suspect threw a rock at the officer and took his gun.

Officer Michael Chesna, 42, a veteran who served in Iraq and Afghanistan, was attending a call about a car accident when he confronted the suspect and was hit on the head with a rock. The suspect, identified as Emanuel Lopes, was later taken into custody after being chased by supporting officers.

Responding to a call about a car driving erratically and crashing into another at 7.30am on Sunday morning, father-of-two Chesna spotted Lopes vandalizing a property nearby. The officer exited his vehicle and called on him to stop.

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“Lopes then attacked Officer Chesna it is believed with a large stone, striking him in the head,” said Norfolk County Assistant District Attorney Greg Connor.

“Officer Chesna fell to the ground. Lopes them retrieved Officer Chesna’s firearm (and) discharged it several times in his head and chest.

“During the foot chase through the yards of Burton Terrace, it is believed Mr. Lopes discharged Officer Chesna’s firearm an additional three times, striking a local resident in her home,” Connor added.

While officials have not publicly identified the second victim, the Boston Globe reports that she was identified on Monday by a relative and her best friend as 77-year-old Vera Adams, a lifelong Weymouth resident.

Lopes was arrested and hospitalized after being struck in the leg in a chase following the attack. He will now face two charges of murder.

“I hired Mike Chesna six years ago tomorrow,” Weymouth Police Chief Richard Grimes told CBS.

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“Officer Chesna has been an Army veteran, and in fact, I was speaking with his mom this morning, and she told me that he joined the military to help open the doors for him to get on this job. He was successful with that … He was just a great family man, he was a great officer.

“He was one of those people who truly sought this job and was fortunate enough to get it.”