More human remains found in Lake Mead amid historic low water levels

More human remains have been found at Lake Mead less than a week after authorities discovered the remains of a man in a barrel amid a drought that has dropped the reservoir's water level to historic lows.

A witness saw human skeletal remains in the Callville Bay area of Lake Mead around 2:00 p.m. on Saturday, the National Park Service said. The Clark County Medical Examiner has not yet identified the cause of death.

Authorities said the investigation is ongoing.

Police warned last week that more bodies could turn up in the country's largest reservoir — located on the border of Arizona and Nevada — after human remains were found in a barrel last Sunday. National Park Service rangers found the barrel with skeletal remains in an area near Hemenway Harbor on May 1 after boaters spotted it.

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The man was found shot and had likely been killed sometime between the mid-1970s and early 1980s based on the type of shoes the victim was found wearing, said homicide Lt. Ray Spencer, the Las Vegas Review-Journal reported.

The bodies have become uncovered as Lake Mead's water level dropped to 1,055 feet, the lowest since 1937, a year after Hoover Dam created the reservoir.

Lake Mead and Lake Powell are the largest human-made reservoirs in the United States, diverting water from the Colorado River to 40 million people in seven states, tribal nations, and Mexico.

Both lakes were full in 2000, but they now are roughly 30% full.

This article originally appeared on USA TODAY: Lake Mead discovery: Human skeletal remains found amid record drought