Wildlife officials said Saturday they found the charred remains of dozens of rare animals in a national park in eastern Borneo, where forest fires are burning.

Doctors warned people, meanwhile, to expect an increase in upper respiratory tract infections if thick smoke and haze from the fires continues to build near the cities of Balikpapan and Samarinda, about 750 miles northeast of Jakarta.Cases of gastroenteritis also would soar if a renewed drought forced people to use unsafe water supplies, they said.

"We could face major health problems if it does not rain soon," said Dr. Jusuf, head of a state-run hospital in Samarinda.

The fires have been burning as a drought grips the eastern part of Borneo island, which should be enjoying heavy rains at this time of year. Meteorologists blame the El Nino weather phenomenon for the delay of the wet season.

A government Hercules C-130 plane dropped a salt mixture into clouds near Balikpapan on Saturday in a bid to draw rain and douse the fires.

Last year, hundreds of fires between July and November across Indonesia produced a haze over much of Southeast Asia, threatening the health of millions. The new fires in Borneo have raised fears the haze might return, perhaps even worse than the last time.

The official Antara news agency reported that rangers in the Kutai National Park, north of Samarinda, had found a large number of remains of orangutans, small deer, snakes and porcupines.