What we know: The shooting of a Southport police officer

Investigators are on the scene at Maynard Dr. and Maddison Ave. near Southport where a Southport Police officer was shot multiple times and transported to Eskenazi Hospital in Indianapolis on Thursday July 27, 2017. The officer was responding to a car accident involving a flipped vehicle shortly before 3 p.m.

A Southport police officer was fatally shot Thursday afternoon while apparently trying to help a victim of a car crash.

As the small community of Southport mourns the loss of Lt. Aaron Allan, investigators have released scant details about what led to the gunfire in southern Marion County.

Here's what we know:

What happened

A blue 2004 BMW 325 crashed and flipped over about 2:40 p.m. in the front yard of a home in the 6600 block of South Madison Avenue a few blocks north of Southport Road in Homecroft. 

Allan, 38, and a Homecroft police officer responded. An off-duty Johnson County Sheriff's Reserve deputy in the area at the time also stopped to help.

Shortly after Allan started to help the crash victims, one of the car's two occupants opened fire. Allan was hit multiple times. The Homecroft officer and the Johnson County deputy returned fire and struck the shooter, authorities said. Both occupants were taken to Eskenazi Hospital and were in police custody.

What prompted the motorist to shoot is unclear.

Allan died later Thursday at Eskenazi Hospital.

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A witness

"He was trying to help," the owner of the home where the car crashed told IndyStar on Friday. The homeowner spoke to IndyStar on the condition that his name is not published.

The homeowner said he had just sat down to watch "The Andy Griffith Show" when he heard two loud noises outside about 2:40 p.m. He thinks the sounds came from the speeding BMW striking his fence and flipping over on his front lawn.

A passenger was out of the vehicle by the time the homeowner got to his driveway. A nurse who was driving by and saw the crash was there trying to help, the homeowner said.

Soon more people arrived, including Allan.

Allan, the homeowner said, crawled into the vehicle to talk to the driver.

"Are you OK," the homeowner heard Allan say.

The Homecroft officer and Johnson County deputy arrived.

In an instant, the homeowner said, the officers became more tense as they focused on the driver.

"They told him, 'Keep your hands where we can see them,'" the homeowner said. 

An arm came out of the driver's side window, the homeowner said, and then the homeowner heard a short burst of gunfire. The homeowner saw Allan duck and try to move out of the line of fire.

A longer burst of gunfire shortly followed, the homeowner said. He presumes it was the sound of the Homecroft officer and Johnson County deputy firing their handguns.

Allan collapsed in the homeowner's front yard. The driver was wounded.

"There was nothing that led up to it," the homeowner said.

The homeowner's account differs from the account a witness told WTHR-13 on Thursday afternoon. She said the shooter was outside of the vehicle when he suddenly jumped up and started shooting. 

Police have declined to clarify the circumstances.

The suspect

Jason Brown, 28, of Indianapolis, was arrested on a preliminary charge of murder in connection with Allan's death, according to an Indianapolis Metropolitan Police Department report.

The passenger, a 20-year-old man, was not arrested. Police on Friday did not call the passenger a suspect.

A search of Central Indiana online court records showed only a handful of traffic tickets and a 2014 Hendricks County misdemeanor charge of marijuana possession for Brown.

The Indianapolis Power & Light building in Downtown Indianapolis on Monument Circle is lit up blue in memory of Southport Police Lt. Aaron Allan and IMPD Deputy Chief Jim Waters on Thursday, July 27, 2017. Both died Thursday — Waters from injuries sustained in a crash on Sunday, Allan from a shooting earlier Thursday afternoon.

The officer

Allan joined Southport police six years ago as an unpaid reserve. In 2015 he was named the department's officer of the year.  In January he joined the police chief as the department's only full-time, paid employees. Allan helped run the department and helped supervise a force of about 40 unpaid reserve officers.

Allan leaves behind a wife and two sons, one of whom had just started kindergarten.

► 'A big teddy bear': Southport community remembers slain officer Aaron Allan

Southport Mayor Russell McClure, who was on the committee that hired Allan, said Allan stood out among the other candidates and was always helping others.

Southport is a community of about 2,300 residents. Allan is the city's first officer to be killed in the line of duty.

Allan's patrol car, parked at the city building, was decorated with flowers and cards after the shooting. The community was still figuring out how to cope with the shock, McClure said.

"It's just devastating," McClure said. "I don't think any words exist to explain what we as a community are going through. It really leaves us speechless."

► Another Thursday loss:IMPD Deputy Chief Jim Waters dies after I-70 crash

Call IndyStar reporter Vic Ryckaert at (317) 444-2701. Follow him on Twitter: @vicryc.