A man attacked people on a hiking trail in Rock Creek Park twice in the past few weeks, and authorities are looking for him, the U.S. Park Police said Friday.

In one of the incidents, the assailant grabbed a jogger’s buttocks, the Park Police said.

In statements, the Park Police said a sex offense was reported Aug. 4 at 3 p.m., and an assault at 7:40 a.m. on Sept. 9.

Both incidents occurred on a trail in the park south of Piney Branch Parkway NW, the Park Police said.

The assailant may have a campsite in the park, near the Valley and Meadowlink trails.

Police released photos Friday that they said showed a man they are looking for.