DALLAS (CBSDFW.COM) – Reginald Kirk is trying to make sense of his sister’s death.

“It definitely hurts. It really hurts,” he said, standing along the 9900 block of Bruton Road, where she died early Sunday morning.

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Family members say 43-year-old Beverly Kirk was leaving her daughter’s home at around 3 a.m., when she tried to cross the street. A passing police cruiser struck and killed her.

“Why didn’t he have his lights on?” asked Kirk.

Police say the officer behind the wheel was following an ambulance to the scene of a disturbance.

The ambulance, they say, had its lights and sirens on; the patrol car, some distance behind it, did not.

In a statement Sunday, a Dallas police spokesperson said, “the officer did not have his lights and sirens activated because it is not required for this particular call assignment.”

In a seemingly similar incident in 2008, a Dallas police officer responding to a late night disturbance struck and killed a 10-year-old boy as he rode his bike into the street.

That officer also did not have lights or sirens on.

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In response, then police chief David Kunkle created a new policy.

“We do not want our officers speeding, violating any traffic laws, unless they’re doing it with their red lights and sirens on,” said Kunkle, in a press conference following the 2008 incident.

The speed limit at the crash site on Bruton Road is 35 miles an hour. Police have not yet said how fast the patrol car was going.

Witnesses, though, claim it was speeding.

“He was going too fast without no lights,” said Tyrone Singleton, who was out for a late night walk.

A neighbor, Eddie Davis, said it’s not unusual.

“Police come through. They fly by all the time,” said Davis.

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Dallas police say they are investigating. The Kirk family, meanwhile, is anxiously waiting for answers.