ANDOVER (CBS) — Authorities are looking for the public’s help with an unsolved murder of an Andover couple found shot to death inside their home nearly four years ago.

Read: 2 Killed In Double Homicide At Andover Home

On the morning of Dec. 14, 2011, investigators found 69-year-old John Magee and 67-year-old Geraldine Magee dead at their Orchard Crossing mansion.

The couple, who was killed just shy of their 40th anniversary, was discovered by their daughter and two grandchildren. She stopped by the house that morning to drop off her kids before going Christmas shopping.

She told police she thought her parents were beyond help, shot to death on the floor. A longtime family friend told WBZ about getting the stunning phone call from the couple’s daughter.

“She said ‘Are you sitting down? My parents were shot and they’re dead,'” she said. “It was a heartbreaking thing to go through.”

The other unexplained part of this story is the couple’s Lexus SUV, found torched on Prince Street in Boston’s North End the night before.

Despite conducting an exhaustive investigation, authorities haven’t been able to track down those responsible for the killings. Prior to this case, Andover Police had only investigated one other murder in the past 25 years, WBZ-TV’s Ryan Kath reports.

Police & DA hold press conference 4 years after the murder of Geraldine and John Magee, their deaths still a mystery pic.twitter.com/6b9cA1wuSM — Susie Steimle (@SusieWBZ) December 7, 2015

Late Monday morning, officials held a news conference in the hopes that people will be able to provide new leads for investigators.

“Someone out there knows something,” said Essex County District Attorney Jonathan Blodgett. “We’re asking you to search your memory and conscience, pick up the phone, and call us.”

The last place John was seen publicly was at Sailor Tom’s Way in Reading, which was a construction site at the time. The real estate developer cleaned supplies from his truck before leaving around 3 p.m. on Dec. 13.

Blodgett says at least 50 interviews have been conducted, and leads have been chased down in four states and more than 20 cities and towns. He also said investigators have reviewed the couple’s personal and business financial statements and area surveillance images.

Andover, Boston, Worcester, and Hampton, New Hampshire police have assisted with the investigation, Blodgett says. Police say everything they’ve heard about the couple was positive.

Police Chief Patrick Keefe says finding the person or persons responsible for “this heinous act” remains a priority for the department.

Related: Family Says Murdered Andover Couple Had No Enemies

The district attorney said he can’t speculate to motive or suspects in the case, according to WBZ NewsRadio 1030’s Doug Cope. Blodgett says the case remains an “active investigation.”

“This is a case that we will not let go cold,” he said. “We will continue to work this until we find the perpetrators.”

On Monday morning, the Magee family released a statement, saying that they hope the suspect or suspects are caught.

Statement from Magee family on deaths of John and Geraldine Magee in Andover 4 years ago. #wbz pic.twitter.com/U6VlyGm5ME — Doug Cope (@dcopewbz) December 7, 2015

“We miss Jeri and Jack very much and not a day goes by without us thinking how blessed we were to have them in our lives,” reads the statement. “But the perpetrators of this crime are still out there and they need to be brought to justice.

“Please help us solve this crime.”

Anyone with information is asked to call Andover Police at (978) 470-3864.

WBZ NewsRadio 1030’s Doug Cope reports



WBZ-TV’s Susie Steimle, Ryan Kath, and WBZ NewsRadio 1030’s Doug Cope contributed to this report.