Butler police continue to investigate an early morning shooting Monday that left a 20-year-old man seriously injured at a Pittsburgh hospital.

Brandon Fairtrace was struck in the face with a shotgun blast while he was in bed at his first-floor apartment in the 200 block of West Brady Street, authorities said.

He remained unconscious and in stable condition at UPMC Presbyterian this morning.

Police said they have at least one suspect but would not say if they have spoken to that person. They also declined to say if they believe more than one person was involved.

A motive “is unclear at this time,” Capt. David Dalcamo said this morning. While police found suspected marijuana in the apartment, Dalcamo said it did not appear the shooting was drug related.

Police learned of the shooting about 4 a.m. after being notified by Butler Memorial Hospital medical staff when the victim showed up there.

Dalcamo said Fairtrace’s girlfriend drove him to the hospital. The woman, who police did not identify, was at the apartment at the time of the shooting but was not injured.

Fairtrace was later flown by medical helicopter to the Pittsburgh hospital.

Police have not spoken to the victim but have been in contact with his family, Dalcamo said.

Investigators have spoken to his girlfriend, who did not see the shooting but was awakened by “a loud explosion,” according to court documents.

She said when she looked at Fairtrace he was covered in blood. She also noticed a hole in the bedroom window.

Police said the shotgun blast was fired from outside the apartment through that window. Police later recovered 46 shotgun pellets and wadding from a shotgun shell in the bedroom.

Dalcamo said he did not know if Fairtrace was targeted in the shooting.

Police said they believe the upstairs tenants were home but were not injured in the shooting. Dalcamo declined to say if police have identified any witnesses.

Investigators later Monday obtained separate warrants to search Fairtrace’s apartment. Police sought the second warrant after finding suspected marijuana and drug paraphernalia in the apartment.

According to an inventory list of items from the apartment, police found at least eight plastic bags containing suspected marijuana, a digital scale and other contraband.

In a safe in the basement, police seized $16,121, documents said.

Dalcamo declined to comment about the search of the apartment and the findings.

“We’re conducting interviews and following leads,” he said.

Butler County Court records showed that Fairtrace last year pleaded guilty to possession of a firearm without a license and reckless endangerment, stemming from a March shooting in Butler.

The incident, allegedly a marijuana sale gone bad, occurred shortly after 3:30 p.m. March 1 near Center Avenue Elementary School.

Fairtrace, who spoke to police, allegedly said he fired one shot into the air after two males in a sport utility vehicle took off with his backpack containing marijuana, according to court reports.

He was sentenced in October to the terms of his plea arrangement: time served to 23½ months in prison. Fairtrace, who had spent more than seven months in prison awaiting resolution of this case, served the minimum end of his sentence.