MONTVILLE, N.J. (CBSNewYork) – A New Jersey community has been struck by tragedy after a boy goes for a swim in a local lake and never resurfaced.

Rescue crews recovered the 12-year-old’s body Wednesday afternoon at Lake Valhalla.

Now investigators are trying to figure out how this happened.

The child gained access to the water through the Lake Valhalla Club in Montville. As other parents showed up to take their own kids for a swim, they saw police and learned why the private club was closed.

“It’s a very close community… he knew how to swim,” one resident told CBS2.

It’s believed the 12-year-old may have gotten stuck under a dock. Dive teams pulled the boy from the water, but he couldn’t be saved.

“It’s heartbreaking, it could be anyone of ours,” Sandy Rivera said.

CBS2 has learned the boy was in an area where the water is 10 to 12 feet deep. There were lifeguards on duty. The police chief – a father of three – reminded everyone that as the summer calendar fills up heartbreak can happen in a second.

“Just really be cognizant of where your kids are, especially when they’re in water,” Montville police chief Andrew Caggiano said.

The Morris County Prosecutor’s Office is in charge of the investigation, but at this point they don’t believe it’s anything other than an accidental drowning and an absolute tragedy.