D.C. Police Sergeant Anthony Mason was fatally shot in Baltimore during a ceasefire early Saturday morning.

Mason grew up in Northeast, DC. He policed for the city he loved for 17 years, and before that he was a marine.

"He loved the city of Washington, and he enjoyed being a police officer and he appreciated life to the fullest," said James Grayton, Mason's cousin.

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Grayton said his cousin spent his life serving his community.

“He wanted to go out and give back and do the things he thought he should be doing as a young man. He saw some of his friends in troubled times, and I think he wanted to give them some support and show that they could do the right thing and that there were some good young men trying to be police officers in DC.”

Mason was off-duty just after midnight Saturday morning. He was sitting in a parked car with a woman in the Walbrook neighborhood of West Baltimore when a gunman opened fire.

He died. The woman was shot in the leg and survived.

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Mason had three children. His youngest is just three years old.

He recently celebrated his 40th birthday.

“His birthday was just about last month," said Grayton. “That was a milestone for him and us too. To see him reach 40 years of age and now he has lost his life. That is a tragedy for this family, and people in the city that lost loved ones in this type of way.”

Mason was on an administrative leave from police work at the time of his death.

MPD Director of Communications Dustin Sternbeck said his death is an extremely sad situation and it wants to be supportive of the family at this moment.

The DC Police Union also expressed its sadness, saying their thoughts and prayers are with Tony’s family and friends.

Mason’s death is now being investigated by Baltimore police. Community activists in Baltimore had called a weekend ceasefire after homicide rates in the city surpassed 300, for the third year in a row.