Denver police are searching for evidence as they investigate the fatal shooting of a policewoman at a city park where families had gathered for a free weekly jazz concert.

Police have taken a person with a gun into custody, but it wasn't clear whether that person was a suspect. The park remained closed Monday while police searched for more evidence.

At least three shots were fired Sunday shortly after the jazz band playing on a lake-side pavilion stage finished, sending waves of people running through park grounds. Police spokesman Sonny Jackson says the officer was shot in the head and died at a hospital.

She was a single mother who had been with the department since 2005.

The slain officer hasn't yet been identified.