Dallas, TX – Dallas Police Department (DPD) Officer Christopher Jackson died unexpectedly after returning home from his shift on July 6.

The 58-year-old officer had just gotten off work and was in the parking lot of his apartment building located in the 2700-block of Duncanville Road when the medical emergency struck at about 4 p.m., CBS News reported.

Officer Jackson collapsed onto the ground, according to WFAA.

An employee at the apartment building and police performed CPR on Officer Jackson until emergency medical personnel arrived at the scene, CBS News reported.

He was then rushed to Methodist Hospital, where he was pronounced dead.

Sources said the veteran officer’s cause of death was a “massive heart attack,” WFAA reported.

Officer Jackson served the DPD for 31 years and was planning to retire next month, Dallas Police Chief Eddie Garcia told KDFW.

He was most recently assigned to the Southwest Patrol division.

“When I walked into that hospital, it was a non-stop conversation with every family member and other officers about how amazing this officer was,” Chief Garcia said. “He was a great man. He’s going to be very sorely missed.”

Dozens of people offered their condolences to Officer Jackson’s loved ones on his memorial website.

“Chris is a perfect example of giving back to the community,” one message read. “As a first responder, a neighborhood policeman, who was dedicated to his role as police officer, son, father, brother, cousin, and friend.”

“My sincere condolences to the Jackson family,” another person wrote. “Earth has no sorrow Heaven cannot heal. Rest in Paradise.”

Officer Jackson was laid to rest on July 15, according to his obituary.

Our thoughts and prayers are with the family of Dallas Police Department Officer Christopher Jackson, both blood and blue. Thank you for your service.

Rest easy, hero. We’ll hold the line from here.