National Park Service rangers responded to Swim Beach around 8 p.m. Monday and worked with the Las Vegas Metropolitan Police Department dive team to set up a perimeter to recover the remains, the park service said in a news release. . He also contacted the Clark County Coroner. CNN reached out to Clark County officials for more information and has not heard back. In addition to those found at Swim Beach, two other sets of remains have been uncovered in the lake since May, including a body being investigated as a homicide after it was found in a corrosive barrel with a gunshot wound, officials said. The homicide victim, whose remains were found May 1, likely died sometime in his mid-70s to early 80s, according to police and Clark County Coroner Melanie Rouse. The victim’s clothing and shoes helped investigators determine the approximate time of death, as some of the clothing was so well preserved that the tags were still visible, police said. Just a week after the homicide victim’s remains were found, a second set was discovered in the lake’s Calville Bay, the park said. Rouse has preliminarily determined that those remains belong to a man estimated to be between 23 and 38 years old, she told CNN previously. The cause and manner of his death are undetermined, he said. The medical examiner’s office is trying to extract DNA from the first two sets of remains in an effort to determine who they belong to, Rouse said. The third set of partial remains was found at Swim Beach on 25 July, followed by more partial remains found in the same area on 6 August. It is unclear whether Monday’s third discovery of remains is related to the previous two partial sets. The remains are beginning to be revealed as Lake Mead’s shoreline recedes dramatically due to prolonged extreme drought in the West. The extreme drought has caused the waters in Lake Mead – the nation’s largest water reservoir – to drop to 27% of its full capacity, threatening the essential water supply for millions of people in the region. As the water level drops, other visitors have been able to see other things that were previously submerged in the lake, including a World War II-era sunken boat and the original 1971 tank intake valve. CNN’s Rachel Ramirez and Ella Nilsen contributed to this report.