KATHMANDU: The death toll from last week’s devastating floods in Nepal has risen to 903, while the number of people reported missing has nearly doubled to 4,247, officials said Monday.

Among those missing are 592 foreign nationals, according to an update issued by Nepal’s National Disaster Risk Reduction and Management Authority. U.S. State Department spokesperson Tommy Pigott said Sunday that around 85 Americans remained unaccounted for.

Rescue teams are continuing to struggle to reach devastated communities days after massive flooding triggered by a glacier collapse in the Nepal-Tibet border region on Wednesday.

“The disaster here is overwhelming,” Ferrin Cole, an operations director with the U.S.-based Crisis Response International, told NBC News on Sunday. “The flood that came down that mountain just wiped out cities. We’re going in as fast as we can to get people the help that they need.”

The disaster has affected more than 90,000 people, according to the Nepal Red Cross.

The scale of the disaster has also overwhelmed morgues in the country. A police officer in Nepal’s Chitwan district told Reuters that more than half of the bodies recovered there were beyond recognition.

China has separately reported 16 deaths and 546 people missing in Tibet, including hundreds of foreign nationals. It remains unclear how much, if any, overlap exists between the Chinese and Nepali missing-person figures.

Nepali officials said more than 10,400 people have been rescued, including 277 foreign nationals.

The response has been further complicated by a landslide-dammed lake above the border checkpoint, which is overflowing, China’s state-run CCTV reported Saturday. However, the broadcaster said the likelihood of a complete breach remained “relatively low.”

Meanwhile, heavy rainfall across Nepal has pushed river levels higher and prompted fresh warnings for communities living along waterways, adding to concerns over further flooding as rescue and recovery operations continue.