MONTVILLE — A 12-year-old drowned Wednesday in the township's Lake Valhalla, according to the Morris County Prosecutor's Office.

The private Lake Valhalla Club is located on the south side of the lake.

News 12 New Jersey reported that the victim was underwater for about 20 minutes before he was discovered. Attempts to revive him were unsuccessful.

The investigation involves Montville Police and the Morris County Prosecutor’s Office.