Montgomery County prosecutors dropped a murder charge Thursday against Bobby Coley, saying there was insufficient evidence to hold him, and sent the 1975 case in which he was implicated to the county police’s cold-case squad for further investigation.

The decision preserves the right to pursue charges later.

But as Coley, of Southeast, walked out of the Montgomery County Detention Center on Thursday night, he flatly denied killing anyone and said he didn’t know of the alleged victim’s 1975 disappearance until nearly a decade after the event.

The decision to drop the murder charge was another quick pivot in a head-spinning two days in which Coley, 63, showed up at the Montgomery County Sheriff’s Office on Tuesday hoping to resolve what he thought was a minor warrant because he was trying to get a job as a custodian at an area hospital.

A records check by deputies found a murder warrant for Coley from 1984, alleging he had been part of a murder-for-hire plot targeting his one-time boss and arranged by the man’s wife. The warrant cited information provided by several confidential sources between 1975, when the wife reported her husband missing, and 1984, when the murder warrant was issued.

Bobby Coley (Montgomery County police)

“I did not do anything. I have no idea why I was put in this case,” Coley said as he tried to pry his driver’s license and ID cards from the packet of personal effects he was handed when he was set free.

Coley said he was “stunned” Tuesday when deputies told him he was being held but that he “didn’t act out. I was there — I mean they weren’t going to let me go — and this needed to be cleared up.”

Coley said he didn’t know there was an active warrant for him in the alleged killing, but he knew his name had come up before because “a Montgomery County detective came to see me when I was in D.C. jail in 1984” and “never came back or never had me shipped out here then.” The address for Coley on the 1984 warrant is “D.C. Jail.”

Coley was jailed in the District between February and December 1984, when the robbery charges he was being held on were dismissed, court records show.

“I feel like, you knew where I was when I was in jail and for the past 38 years, and now you done come to me when I’m 63 years old? They knew where I was all this time,” Coley said.

Told that the Montgomery case was still being investigated, Coley said,: “They can investigate me for the rest of my life. I had nothing to do with this. That man was good to me.”

The alleged victim — whose body has never been found and who has not been heard from since 1975 — was Leopold Chromak, then 29.

In the old warrant, a detective said sources had told him Frances “Ricky” Chromak arranged to have her husband killed after he abused her. The alleged murder was done by men who worked for the couple’s business, the warrant said, and named Coley among those.

Coley said he worked for about five months for Chromak’s painting company in 1975 and left “during the summer” to take a new job as a custodian at an apartment building. He said Leopold Chromak wasn’t missing when he left.

During a District Court appearance Wednesday in Rockville for Coley, prosecutor John Feeney told a judge that “quite candidly we cannot tell you what the viability of this case is at this point.”

Judge Eugene Wolfe held Coley without bail and gave the state a week to come back with additional facts if it wanted to continue to detain him.

The state was back in a day to drop the charge.

On Wednesday, authorities said it was not clear whether Frances Chromak or anyone else had been charged before, and detectives were scrambling to dig up details.

Feeney said in court that Frances Chromak is thought to be alive.

For the past two days, The Washington Post was not able to find a working phone number or current address or relatives of Frances Chromak’s who knew her whereabouts.

County police are “beginning to look into the case anew with Mr. Coley and other factors that I’m not able to discuss,” Capt. Paul Starks, a spokesman, said Thursday night.

A spokesman for Montgomery County State’s Attorney John McCarthy declined to comment beyond the brief announcement of dropping the case.