A woman and two children have died and two others were hospitalized after a pontoon boat capsized on Lake Powell in northern Arizona, authorities said Sunday.

National Park Service officials said the privately owned 25-foot pontoon was being towed by another boater when it was overturned by waves Friday afternoon near the mouth of Navajo Canyon within Glen Canyon National Recreation Area.

Lake Powell is located northeast of Page and near the Arizona-Utah border.

Emergency crews responded to the scene and found some of the 11 passengers atop the overturned pontoon and others in the water and trapped underneath the boat.

Glen Canyon rangers and Page Fire Department personnel help get the injured out of the water and into ambulances and helicopters to be rushed to hospitals. The Coconino County Sheriff’s Office, which also responded to the incident, posted an image of the capsized boat on social media.

Authorities said Saturday that 72-year-old Melissa Bean and two 4-year-old boys died at the scene.

The names of the boys haven’t been released yet.

Authorities said two other pontoon passengers remained hospitalized Sunday – a 12-year-old girl in critical condition and a man being treated for undisclosed injuries.

It remains unclear if any of the victims were related, but authorities said families from Utah and Idaho were on the pontoon when it capsized.

The incident is being investigated by the county sheriff’s department, National Park Service and county medical examiner’s office.

“It’s not unusual for us to investigate a death on the water periodically throughout the year. However, the magnitude of this – we’ve got three fatalities and two in critical condition – is not a common circumstance and it’s definitely tragic,” Lt. Adam Simonsen, a spokesman for the Coconino County Sheriff’s Office, said in a statement.

The National Park Service said multiple agencies helped in the operation — Big Water Fire assisted dispatch and Kane County Sheriff’s Department helped in providing information while rangers and other personnel responded to the incident.

“The National Park Service and Coconino County Sheriff’s Office express their condolences to the families,” the park said.

Lake Powell is one of many bodies of water in the U.S. West that has suffered from years of drought. In 2022, satellite images showed the dramatic impact of the mega-drought that left the lake just 24% full.  At the time, the National Park Service was forced to shut down 11 boat ramps at the Lake Powell recreation area, which draws millions of visitors.