VOLCANO HITS JAPAN LEAVING31 HIKERS DEAD!!!

Mount Ontake, Japan (CNN) -- At least 31 people are presumed dead after rescuers found them showing no signs of life Sunday near the summit of a Japanese volcano that started erupting a day earlier.

Police said the people were in a state of "cardiac arrest," meaning that they were discovered without a pulse and weren't breathing but hadn't been declared dead by a doctor.

A coroner confirmed the first four deaths Sunday.

Rescue teams had begun searching Sunday for dozens of climbers who were caught by the sudden eruption of Mount Ontake.

The volcano in central Japan unleashed a huge cloud of ash late Saturday morning that billowed down the mountainside and engulfed hikers in its path. Witnesses described hearing a sound like thunder when the eruption began.

The exact number of people unaccounted for was unclear, as officials were uncertain how many had already made it off the mountain.

Desperate relatives

Relatives of the missing gathered near Mount Ontake on Sunday desperately seeking information. Among them was Kiyokazu Tokoro from nearby Aichi prefecture, whose son, Yuki, was hiking on the volcano with his girlfriend.

He said he knew they were near the summit at the time of the eruption because his son's girlfriend had sent a photo to a friend minutes beforehand.

"All I can do is beg for your help to get information," he told CNN. "Please help us."

Authorities estimated there were 200 to 250 hikers in the area at the time of the eruption. Most of them were reported to have managed to make the long trek down the mountain.

But some people remained trapped in several lodges on Mount Ontake, and others were missing altogether, local authorities said.

More than 350 rescue workers -- a mix of police, firefighters and military personnel -- began climbing two separate routes up the mountain on Sunday morning, authorities in the nearby village of Otaki said.