MONTGOMERY COUNTY, Md. -- Robert Lee Miller Jr., 44, was a Maryland businessman when he was slain 30 years ago.

Detectives said he was having some money problems and that those problems might have brought him together with his killer.

Miller was president of Interstate Bridge Company when he was killed on May 9, 1978.

Police said that the company had been having financial difficulties for about a year.

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News4's Joe Krebs reported that Miller often wore expensive cowboy boots, western suits and Stetson hats, and carried a gun.

"He was known to carry a weapon with him," said Detective Edward Golian of the Montgomery County police. "He had a permit for it."

Golian said on the day Miller was killed in Room 421 of what was then the Ramada Inn on Route 28 and Interstate 270, he had about $1,900 on him.

Krebs reported that on that day, Miller checked into that room apparently thinking he was going to meet someone to talk about a business deal. Instead, it was an elaborated setup for someone to kill him.

A chauffeur drove him to the hotel about 6:30 pm.

Miller checked in and went back to the parking lot to get some business papers. Police said that as he was heading back into the lobby of the building he grabbed a bottle of Jack Daniels from his car, and his gun.

After Miller returned to his room, a man with an Italian or Armenian accent asked the front desk clerk for Miller's room number. About two hours later, Miller was found dead on the floor.

"One theory is, in Miller's mind, he was probably meeting a man who was going to help him out financially and help him get out of the burden he was going through at the time," said Golian.

The two men apparently poured drinks, talked, and relaxed, according to police.

Police said the gunman picked the right moment to surprise Miller from behind. He was shot once in the back of the head.

The chauffeur saw a man walk out of the hotel calmly, get into a small brown sports car and leave.

Police said the killer left evidence behind, including what they believe are fingerprints taken off a glass that was possibly handled by the shooter. Those prints have not yet been linked to anyone.

"Someday, we hope that if this person was ever arrested and fingerprinted, we'd be able to identify him," said Golian.

Investigators said they want to hear from anyone who knows anything -- perhaps something learned from the shooter himself.

"As time goes by, you get a little confidence that you've completely gotten away with this, and you may mention it to someone," said Golian.

The Montgomery County Police Cold Case Squad would like people with information on this case to call 1-866-411-TIPS.