A Baltimore man has been accused by police of donning a disguise and gunning down a millionaire philanthropist at a nursing home on Valentine’s Day and later firing at a Maryland state trooper during a traffic stop.

Maurquise Emillo James, who is 22 and goes by “Malquazy,” has been charged with first-degree murder in the Feb. 14 killing of 87-year-old Robert Fuller Jr., according to police charging documents.

James has also been charged with with attempted first-degree murder, felony assault, using a firearm during a crime of violence, and related offenses for allegedly opening fire Tuesday on the trooper, who was not seriously injured, the documents show.

What investigators don’t have is a motive.

Fuller lived at a Cogir senior living center in Potomac, Maryland, where James worked as a medical technician on the night shift, according to the documents.

“We do not have a good sense of why he shot and killed Mr. Fuller,” Montgomery County Police Captain Sean Gagen said during a press conference Wednesday. “Upon speaking with him, he said their relationship was very good and he would have never hurt Mr. Fuller.”

But police said that when they searched the suspect’s home they found several wigs and a mask.

James was being held Thursday at the Montgomery County Correctional Facility, jail records show.

Fuller, a retired Navy Reserve officer who donated millions of dollars to help support numerous institutions in Augusta, Maine —where he formerly worked as a lawyer — was found shot in the head in the apartment at the facility he shared with a partner, according to the court documents.

Under questioning, the partner told detectives that James gave Fuller his usual dose of the painkiller Oxycodone on the night of Feb. 13.

But the partner, who is not identified in the charging documents, said James then came back later and asked Fuller if the medication “had kicked in yet.”

The partner told detectives that was “very odd” because James didn’t usually come back after giving Fuller his meds.

Informed that Fuller had been shot, the partner expressed surprise the gunshot didn’t wake them up because “his/her hearing was excellent,” the charging documents said.

James confirmed he had given Fuller his medication and continued working at the facility while detectives investigated Fuller’s murder.

Later that day, detectives obtained surveillance footage from around 5 a.m. that showed a person wearing what appeared to be a mask and wig, as well as a “unique” plaid jacket, walking toward a rarely used side entrance of the building.

The person was seen opening the door and entering into a stairwell.

About 12 minutes later, the charging documents say, the same person was seen leaving through the door and “running down the sidewalk.”

Detectives later discovered that the door had been propped open with a folded paper towel and the battery had been removed from sensor that would have sounded an alarm.

They also began to suspect that the murder might be an inside job, because whoever killed Fuller “had access to the building,” the charging documents say.

Last week, on Feb. 20, police made public a short clip of the surveillance footage and a press release that noted the suspect’s “unusual gait” and jacket.

On Sunday, the vise around James began to tighten after an unidentified tipster told police that the person in the video had a familiar gait and might work at the facility, according to the charging documents.

Then, on Monday night, a supervisor at Cogir noticed James was still at the facility long after his shift was over and asked him why he was still there.

“James then quickly grabbed his items and left,” the charging documents said. At 3 a.m. Tuesday, a state trooper pulled over “a silver Infiniti sedan with no tags.”

When the trooper began approaching the vehicle, the driver “shot at the trooper” and took off. The trooper did not return fire.

Police arrested James on Tuesday afternoon in Rockville, Maryland for shooting at the trooper, Gagen said. He was later charged with the Fuller murder after the matching a shell casing from from the trooper shooting to the gun used to kill the elderly man.