Aug. 31 (UPI) -- The National Park Service confirmed Monday that two people died and about 15 people were believed missing Monday in Grand Canyon National Park after it was hit with a flash flood over the weekend.
The body of a 46-year-old man was discovered along the Colorado River near Crystal Rapids on Sunday evening. The National Park Service said Monday that a second body has been recovered as search and recovery efforts were underway.
"Preliminary assessments indicate approximately 40% of the Transcanyon Waterline was damaged or destroyed," the Grand Canyon National Park Service posted on social media.
The National Park Service said earlier on Monday that it believes about 15 more people were missing as hiker access throughout Bright Angel Creek has been cut off due to "nearly all footbridges" being being destroyed.
Areas of the Grand Canyon began to flood on Saturday afternoon with heavy rainfall recorded in Bright Angel Canyon and Phantom Ranch. These locations are the only places that offer lodging under the rim of the Grand Canyon and Phantom Ranch may only be reached on foot, by mule or by rafting down the Colorado River.
More rain was expected Monday.
"After recent heavy rain and significant flash flooding, the regions is extremely vulnerable, so any additional heavy rain today will likely lead to flash flood impacts, which locally could be significant," the National Weather Service's Prediction Center said.
The area was under a Level 3 threat of flooding, the second-highest threat level meaning that numerous flash floods were likely.
"Grand Canyon National Park staff, in coordination with the Arizona Department of Public Safety, are continuing evacuation and response efforts and working to account for individuals who may have been in the affected area," the National Park Service said in a statement.