DALLAS (AP) — The Dallas Police Department allowed an officer to continue patrolling for more than a year while investigating whether he ordered two people to be killed because it didn’t want to tip him off, the city’s former police chief said.

U. Renee Hall, who left the department at the end of 2020, said in a statement posted on Twitter late Thursday that police investigators, in collaboration with the FBI, recommended not placing Officer Bryan Riser on administrative leave after he was identified as a person of interest in 2019.

“Taking that action could have compromised the investigation. If Riser had known he was a person-of-interest, DPD might not have been able to bring justice to the families,” Hall said.

Hall’s explanation came hours after Riser, 36, was arrested on two counts of capital murder. Riser was being held Friday on $5 million bond after a court appearance Thursday night.

Court records don’t list an attorney for Riser, who told the court he would hire one.

Hall said that when Riser was first identified as a person of interest, police working alongside the Dallas County district attorney’s office, determined there wasn’t yet enough evidence to charge him.

“It took persistence and months of dedication to accomplish, and the people of Dallas are safe because of it,” Hall said.

Dallas’ new police chief, Eddie Garcia, said that someone came forward in 2019 and told police he kidnapped and killed two people, 31-year-old Liza Saenz and 61-year-old Albert Douglas, on Riser’s instructions in separate 2017 attacks. Garcia said neither killing was connected to Riser’s police work, but that investigators were still trying to determine the motives.

Garcia, who became chief last month, didn’t explain why Riser was arrested nearly 20 months after the witness came forward, and police declined to answer subsequent questions about the timing. Both victims were shot and their bodies were dumped in the Trinity River, according to investigators. Saenz’s body was recovered, but Douglas’ wasn’t.

Three men were charged with capital murder in the killing of Saenz: Kevin Kidd, Emmanuel Kilpatrick and Jermon Simmons. Kilpatrick is serving life in prison for the killings of a father and son. Kidd and Simmons are jailed on capital murder charges stemming from the killings of Saenz and the father and son. Simmons is also charged in another death.

One of the men charged with Saenz’s killing told police that he and Riser were involved in burglaries when they were young, according to an affidavit for Riser’s arrest that doesn’t identify the man by name.

More recently, Riser and the man allegedly hatched a plan to rob drug stash houses, but they didn’t follow through with it, according to the affidavit. Instead, the man told investigators that Riser offered to pay him a total of $9,500 to kidnap and kill Douglas and later Saenz, the affidavit says.

The affidavit states that Riser told the hired killer that Saenz was an “informant,” though it doesn’t elaborate and police declined to answer questions about whether Saenz had some connection to the department.

Riser is on administrative leave pending the outcome of an internal affairs investigation. Garcia said his department would expedite the process of firing him.