— The parents of a Jewish Democratic National Committee staffer killed near his Washington, D.C., home this summer have called on the public to help them find his killer.

Seth Rich, 27, was killed while walking home before dawn on July 10. Police have speculated that he was the victim of a robbery gone awry. Rich’s body was found about a block from his home with his wallet, watch and cell phone still in his possession.

His parents, Mary and Joel Rich of Omaha, Nebraska, arrived in Washington on Monday in an attempt to find new leads in the case.

In a news conference, they upped the reward for information leading to their son’s killers from $25,000 to $125,000. The $100,000 was put up by Washington Republican lobbyist Jack Burkman.

“D.C. is like a political fraternity. This could have happened to any one of us, it could have happened to my Republican staff, it could have happened to my Democratic staff. I have people working for me and often in those same neighborhoods so it’s just something that tugs on your heart strings,” Burkman told reporters.

Seth Rich’s Parents Ask Public’s Help in Solving Son’s Murder

Rich’s parents revealed new information in the case during their news conference, including that Seth Rich was on the phone with his girlfriend up until a couple minutes before he was shot dead by at least two bullets, likely from a revolver.

The couple has also, for the second time, asked the public not to traffic in lies and conspiracy theories about their son’s murder, including one connected to Wikileaks that points a finger at the Clintons and says that Seth Rich was meeting with the FBI over Hillary Clinton’s presidential campaign.

Seth Rich served as the voter expansion data director for the DNC, and worked on databases to help voters identify polling stations, the Washington Post reported. Colleagues told JTA that he was also engaged in Jewish outreach.

Seth Rich’s Parents Ask Public’s Help in Solving Son’s Murder