Authorities said a teenage girl was killed after a man she was dating forced his way into a residence in Arcadia and shot her. The man then fled and attempted to take his own life in a shooting in Pasadena, officials said.

A witness told The Times there were multiple people who saw the Pasadena shooting, which took place on a sidewalk in broad daylight.

On Thursday around 11 a.m., Arcadia police responded to a call about a possible shooting in the 800 block of West Huntington Drive. The caller said a man was inside the residence and had fired a gun.

Officers arrived to find a girl with a gunshot wound, according to a statement Thursday afternoon from Arcadia police. She was pronounced dead at the scene.

By the time officers arrived, the man, identified by the Los Angeles County Sheriff’s Department as 20-year-old Paul Anthony Cruz Jr., had fled the scene, according to the statement. Arcadia police did not share the victim’s name.

The case remains under investigation and is being handled by the Sheriff’s Department Homicide Division, according to Arcadia police.

Authorities believe the man fled to Pasadena, where he attempted to take his own life about an hour later.

The Sheriff’s Department said Cruz was in a dating relationship with the victim. He had “forced entry” into the Arcadia location, according to the department.

Pasadena city spokesperson Lisa Derderian said the man was found with a self-inflicted gunshot wound in the city on Thursday about 12:30 p.m. and was transported to a hospital in critical condition.

The Sheriff’s Department said he shot himself as Pasadena Police Department officers were preparing to contact him. He remained in critical condition as of about 7 p.m.

Michael Amini, manager at Alliance Auto Body Works on South Arroyo Parkway, told The Times he was working across the street when the Pasadena shooting took place. The neighborhood was “pretty busy” at the time, and there were several other witnesses, he said.

The suspect, who was being pursued by police, parked his car in the Petco parking lot, walked over to the sidewalk and pulled out the gun, Amini said.

After the shooting, Amini said, he saw the man lying face down. Police arrived about “five seconds” later, he said.

“It was really fast,” Amini said.