LAS VEGAS (KLAS)– Another set of skeletal remains was discovered at Lake Mead on Saturday morning, the National Park Service said.

National Park Service Rangers received an emergency call reporting the discovery of human skeletal remains at Swim Beach in the Lake Mead National Recreation Area around 11:15 a.m.

Rangers responded to recover the remains with help from a dive team from the Las Vegas Metropolitan Police Department.

The cause of death and the identity of the remains has not been determined, and no other details have been released.

This is the fourth discovery of human remains at Lake Mead since May. The first set was found May 1 when a body was found in a barrel near Hemenway Harbor.

Less than a week later, additional human remains were found at Callville Bay. The third set of remains was found on July 25, when a person at Swim Beach near Boulder Beach reported human remains to the National Park Service.

One man, Las Vegas native Todd Kolod believes the remains found at Callville Bay could be his father who died more than six decades ago. Nexstar’s KLAS reports Kolod was 3 years old when his father Daniel, then 22, drowned in Callville Bay in 1958. His body was never recovered.

Investigators have not confirmed the identities of the remains found at Lake Mead this summer, including those found at Callville Bay.