ADAMS TWP — An unknown killer — or killers — wanted Tara S. Bouie dead.

“It appears to be an execution-style shooting,” state police Lt. Eric Hermick said.

There was no sign of robbery. And the method of the killing — a single gunshot to the side of the head — discounted the possibility that it was a crime of passion.

Still without an arrest, investigators continue piecing together leads while trying to unravel the motive behind Bouie’s slaying last week in her rental home in a rural section of Adams Township.

Police said they have no suspects but acknowledged that a key focus of the investigation is whether the 42-year-old Bouie was shot because her boyfriend is jailed on charges he fatally shot one man and wounded several others, all members of a Pittsburgh motorcycle club.

“Retaliation is one of the theories that’s being looked at,” Hermick admitted.

A friend discovered Bouie’s body about 11:30 p.m. Wednesday after going to the victim’s house on Tenacity Trail to check on her. That friend, who was accompanied by his girlfriend, immediately called 911.

Township police found Bouie lying face down in a pool of blood, authorities said.

Police recovered a slug near the body. but it was so damaged that investigators could not immediately determine the caliber.

Next to Bouie was her 5-month-old daughter, unharmed and in a child seat.

The seat belt was “tied in a knot instead of being buckled,” according to a police report, suggesting the child “was tied into the seat so she could not get out.”

Investigators believe the baby was at the home when her mother was shot. The girl may have been alone with her dead mother for as many as 12 hours.

Hermick said there was no sign of forced entry. The house was not ransacked and nothing appeared to be missing. Money and cell phones were found.

Except the gunshot wound, Bouie had no other injuries.

Police said they found no guns, no drugs or other evidence of any suspected criminal activity.

Bouie’s neighbors told police they did not hear any gunfire or see anything suspicious.

Police continue to interview those who knew Bouie and Harrison. Additionally, they are awaiting the results of a range of scientific tests, including ballistics, fingerprint and forensic analysis of trace evidence.

Hermick said that investigators met Monday with representatives of the county district attorney’s office for “prosecutorial guidance” in their investigation.