Authorities in Ocean County say the investigation into a March forest fire in Lakewood and Brick townships has stalled due to uncooperative witnesses.

The Ocean County Prosecutor’s Office determined soon after the March 14 blaze that it had been deliberately set. Since then, Prosecutor Bradley Billhimer says investigators have attempted to question about 60 people, most of whom have been uncooperative. As a result, the ongoing investigation is at an impasse.

The fire burned 167 acres and jumped across the Garden State Parkway, forcing hundreds of people in both municipalities to evacuate. A firefighter sustained a heart attack while battling the blaze.