Amid spate of deadly falls at Grand Canyon, officials say over-the-edge fatalities are rare

A string of deadly falls at the Grand Canyon in recent weeks has garnered public attention and national headlines. But officials say over-the-edge fatalities are actually pretty rare -- and that this year's total isn't unusual.

Some 6 million people visit Grand Canyon National Park in Arizona every year, and just 17 will die from myriad causes.

Some of the more common causes include cardiac issues and heat-related medical issues, according to Grand Canyon National Park spokesman John Quinley.

The average number of those who die falling from the edges of canyon rims within park boundaries is typically in the low single digits, between zero and four per year, Quinley added.

"Some were clearly accidents, others are determined as suicides and others are unknown," Quinley told ABC News.

So far, a total of five visitors have died inside Grand Canyon National Park this year, including two who fell from the rim this month.

A 67-year-old man died April 3 after falling about 400 feet from the South Rim. A 70-year-old woman died Tuesday after falling some 200 feet from the South Rim. It's unclear what caused their falls.

A tourist from Hong Kong died falling over the rim into the canyon within the Hualapai reservation, just outside the national park's boundaries, on March 28. He was taking a photo at the time, authorities said.

More than 318 million people visited U.S. national parks last year, and the Grand Canyon is among the most popular. The number of visitors to has surged over the past five years, from 4.7 million in 2014 to 6.3 million in 2018, according to Quinley.

On average, six people die every week in national parks, at national monuments or other conservation or historical properties within the park system.

There were a total of 265 search-and-rescue incidents at the Grand Canyon last year, below the 10-year average of 294, Quinley added. The incidents cover a wide range of events, from helping fatigued hikers to recovering fatalities.

The National Park Service encourages all Grand Canyon visitors to stay on designated trails and walkways, always keep a safe distance from the edge of the rim and stay behind railings and fences at overlooks.

ABC News' Rebecca Patterson contributed to this report.