A Baltimore homicide detective was fatally shot in the head with his own gun after a struggle with his killer last week, the city’s police commissioner said Wednesday.

Sean Suiter, 43, was to testify before a grand jury the day after he was killed, Commissioner Kevin Davis said. The grand jury is looking at a corruption case involving several Baltimore officers who were federally indicted in March.

Suiter, an 18-year department veteran, was investigating a killing in west Baltimore on November 15 when he saw a man exhibiting suspicious behaviors, police said. The officer died the next day at a hospital.

In an apparent attempt to address speculation about a connection between Suiter’s killing and his pending testimony, Davis said the Suiter and his partner were not lured to the scene of the shooting and made a “spontaneous decision” to investigate the suspicious man.

“It certainly makes for great theater,” Davis said. “We have a police officer who’s shot and killed and we don’t have a really good description, and we don’t have someone in custody — and lo and behold … I found out after the fact that he was scheduled to testify in front of a federal grand jury.”

Davis added: “I understand the speculation that exists. … It’s our responsibility really to follow the evidence and there’s no evidence whatsoever.”

In March, several Baltimore officers, members of the department’s Gun Trace Task Force, were accused in a federal racketeering indictment of robbing people, claiming fraudulent overtime and filing false affidavits.

Davis said federal officials told him “in no uncertain terms” that the father of five was not the target of any ongoing criminal investigation.

“There is no information that has been communicated to me that Detective Suiter was anything other than a stellar detective, great friend, loving husband and dedicated father,” Davis said.

The officers first saw the killer acting suspiciously about 20 minutes before Suiter’s fatal encounter, police said.

Davis said Suiter struggled with his killer, making a brief call on his police radio at the time of the killing, Davis said. Suiter’s clothing indicated he and the killer had struggled, Davis said.

The officer was found with the radio still in his hand, the commissioner said.

“It’s unintelligible right now,” Davis said of the radio call. “We don’t know exactly what he said but he was clearly in distress,” Davis said, adding that the FBI is working with the department to enhance the radio transmission.

There was also the apparent sound of gunfire in the background of the radio call, Davis said. Suiter’s partner, also a detective, took cover across the street and called 911 when the gunfire erupted, Davis said.

Suiter was shot in the head at close range, the police commissioner said. The officer’s DNA was found on the fatal round recovered from the scene, Davis said.

The reward for information leading to the arrest and conviction of Suiter’s killer has grown to $215,000.

Earlier in the week, Davis said he believed the killer was still in the city and he may be wounded.

Suiter’s funeral is scheduled for November 29, Davis said.