Police in suburban Romeoville say that a suspect in the shooting deaths of a family of four has died after a crash in Oklahoma, sending shockwaves through the Streamwood neighborhood where he lived.

Nathaniel Huey Jr., 31, was identified as a suspect in the shooting over the weekend, and when authorities attempted to arrest him in Oklahoma, he attempted to flee, crashing his vehicle.

The car burst into flames, and police reported at least two gunshots. Huey was pronounced dead at a local hospital, and a woman, identified as a person-of-interest in the case, died Wednesday afternoon, her attorney told NBC Chicago.

On Wednesday, police put up crime-scene tape around Huey’s home, leaving neighbors in shock over his alleged actions.

“He seemed like a normal, nice guy to me. Never would have suspected anything,” Susan Hallas said.

Police say that evidence in the case “showed them a nexus” between Huey and the victims in the case, something that stunned neighbors who described a quiet individual who kept to himself.

“I don’t know where things went bad, or where they went sideways,” Alex Hernandez, the nephew of the woman identified as a person-of-interest in the case, said. “I spent Thanksgiving here. I leave my kids here sometimes. It’s like, my mind is lost right now.”

The family of four victims shot and killed inside a Romeoville residence over the weekend is speaking out for the first time, thanking supporters and police for their work in the case.

Zoraida Bartolomei, Alberto Rolón and their two sons were shot and killed inside their Romeoville home at some point between 9 p.m. Saturday and 5 a.m. Sunday, according to police.

Authorities discovered the victims Sunday during a well-being check.

Wednesday morning, a digital license plate reader alert in Oklahoma noted a suspected vehicle related to Huey was detected in Catoosa, Oklahoma, police said. Authorities there attempted to stop the vehicle and the driver “immediately attempted to elude the officers, resulting in a single-car crash,” Burne said during a press conference Wednesday afternoon.

The vehicle ultimately caught fire and officers at the scene reported hearing noises, believed to be two gunshots, before discovering Huey dead in the driver’s seat and the woman critically wounded in the passenger seat, Burne said. Both had gunshot wounds.

“This is still an active and evolving investigation and this portion of the incident is still unfolding,” Burne said.

Burne did not specify on the relationship between Huey and the family, but said evidence “has shown us a nexus between our suspect and the victims, as well as a possible motive.” He declined to comment on the possible motive, however.