Honolulu police say two men in their 40s were arrested last week after state conservation officers heard gunshots at the Waianae Kai Forest Reserve.

The Honolulu Police Department and state Department of Land and Natural Resources officers teamed up to arrest a 48-year-old man for the alleged possession of a loaded AR-15-style rifle that turned out to be a ghost gun with no serial number.

Police seized the ghost gun and arrested the man — and subsequently charged him — with multiple firearms offenses.

Police also arrested a 44-year-old man who allegedly assaulted one of the responding HPD officers, causing bodily injury. The man was later charged on suspicion of second-degree assault on a law enforcement officer.

“As a result of this cooperative effort with our state law enforcement partners, a ghost gun has been taken off the streets,” said HPD in a news release. “HPD and DLNR will continue this work to ensure the safety and security of the public.”

The DLNR enforcement hotline is available at 808-643-DLNR to report suspected illegal activity involving natural, cultural and historic resources.