Mayor Mufi Hannemann has urged the public to be more vigilant about reporting suspicious activities in their neighborhood parks in the wake of two reported sexual assaults this week - one in downtown Honolulu and the other in Kapolei.

Hannemann called the acts "outrageous" and "deplorable."

"We obviously want to redouble our efforts to see how we can prevent this from happening," the mayor said, stating that he will talk to parks and police officials.

Ultimately, however, the community needs to be "the eyes and ears," Hannemann said. "They need to report these situations before these acts occur. If they're seeing illicit activities taking place, if crowds of rowdy young people (are) getting together and doing these, you know, whatever it is, in these parks, let us know beforehand. If we need to send out a 911 call ... let's do that."

"We've got to be much more proactive. I really would encourage people who live in these areas, when they see these things happening, to let the proper authorities know."

The two incidents put everyone on alert, he said.

"We've had two incidents occur in two parks, so it's very much top of mind," he said. "We don't want to see this happening again. And we'll do everything we can to make sure that that kind of behavior is not tolerated at all in this community."

Police are investigating the case of a reported sexual assault by a group of boys on an 11-year-old girl Tuesday night at Beretania Community Park on 'A'ala Street. The girl told police she knew her attackers from school, but there have been no arrests.

A 19-year-old 'Ewa Beach woman reported being sexually assaulted Wednesday evening at Kapolei Park.

She told police she was using a restroom at about 5:30 p.m. when she was hit from behind and assaulted. Police have no description of the assailant.