Waterford — The mystery of Kyle Seidel's murder remains unsolved, but reminders of his death are everywhere, even in prison.

"Whenever an inmate plays cards, the five of diamonds is Kyle Seidel," Waterford Police Lt. Tim Silva said. "The only cards they can use is a specific deck with unsolved homicides on them."

Silva credited the state's cold case unit for coming up with the idea — the cards have a short description of what happened to the victim, a photo of the the person and a phone number to reach Connecticut's cold case unit.

Reminders of the Seidel case exist on Facebook, too: Waterford Police published a photo of the playing card on its Facebook page Saturday, seven years to the day since Seidel died.

The photo was accompanied by a post imploring people to relay information related to the homicide. Seidel, who was married with three children at the time of his death, was shot in the chest on Dec. 21, 2012. He died in the former Family Bowl bowling alley parking lot.

Seidel, who worked at a marina, was described as a family man and homebody by his mother, Darlene Seidel.

"Those who may have information or details about any activity in the area of the former Family Bowl property or may have witnessed either the victim or his vehicle, a black Ford Focus, are urged to call the Waterford Police Department at 860-442-9451 or call the detectives directly at 860-442-0645," the post read.

People can also email cold.case@ct.gov, call the Cold Case Tip Line at 1 (866) 623-8058 or the Waterford Police Anonymous Tip Line at (860) 437-8080. Silva said the state cold case unit based in Rocky Hill is leading the probe into Seidel's death. Waterford Police and the New London County States Attorney's Office are also involved in the effort.

So why seek additional information now?

Silva said publishing the post on the seven-year anniversary was a symbolic gesture, but the call for more details is real.

"We have some active leads, we have a direction that the case is going, but there's still some pieces that we need, and we know that there are people out there that have information that they just haven't shared yet," Silva said.

While Silva avoided specificity, he did say he felt authorities were closer to an arrest than they were in the couple of years immediately following the murder. Police recently met with the family to update them on the investigation. Law enforcement wants the public to know this is still an ongoing matter.

"It is something we hope to keep in the forefront of people's minds," Silva said. "The bowling alley isn't even there anymore; we don't want people to forget about it."

The Family Bowl has been replaced with an Aldi supermarket — one less reminder of Seidel's murder.

"The bottom line is, we need the public's help," Silva added. "There's somebody out there that has information, and we need them to have the courage to bring it forward."

In 2014, former Gov. Dannel P. Malloy authorized a $25,000 reward for information leading to an arrest and conviction in the death of Seidel at the request of Michael L. Regan, state's attorney for the Judicial District of New London. Silva said that reward is still available.

Seidel's wife, Kate, and his mother both posted tributes to his life on Facebook on Dec. 21.

"7 years, it seems like yesterday my heart was broken forever. I miss you more every day! Few words are left to say except I will love you forever and always, Mom," Darlene Seidel wrote in the Justice For Kyle Seidel Facebook group.

"A lot has happened since this night 7 years ago when Kyle was murdered. Our lives were shattered and I was left to pick up the pieces," Kate Siedel wrote on her personal page. "But here we are 7 years later and we are doing good. We have been blessed in many other ways ... It has also been 7 years that Kyle's killer has been walking free. This scumbag knows who he is, knows what he did and knows that he will get caught."

Questions about Seidel's killing linger. Aside from who killed him and why, there is the question of why Seidel stopped at Family Bowl while on his way to pick up Chinese food.

Silva said police are working to find answers to these questions and others.

"The longer a case stays out there, the more information you need to bring it to a successful resolution," Silva said. "The resolution really is just getting to the truth."

s.spinella@theday.com