More than 400 people canceled reservations at hotels and inns in Aso, Kumamoto Prefecture, on Tuesday, a day after Mount Aso erupted and turned the sky ashen. Businesses relying on tourism voiced concern about the financial fallout.

The Meteorological Agency maintained its alert level at 3, which prohibits people from going up the mountain. It also warned residents of the risk of falling rocks and pyroclastic flow across an area up to 2 km from the crater.

The plume of smoke and dust that rose 2 km into the sky at one point Monday was less than a quarter of that size Tuesday.

The Meteorological Agency's Fukuoka branch predicted no major fall of ash because the plume was low.

"Accommodation premises are located a safe distance away, about 10 km from the crater," an Aso city tourism official said. "We want to make sure damaging rumors don't spread."

Land minister Akihiro Ota told a news conference that the government will do its utmost to provide accurate information to minimize the effect on tourism.

Some enterprises seem likely to suffer. Spots on the tourist trail such as the Aso Volcano Museum and a horseback riding club are located only about 3 km from the crater. Both are popular with Japanese and foreign visitors.

Many tourists visiting there Monday morning were forced to evacuate later in the day after the area became a no-go zone.

But many tourist spots, including hot springs, lie outside the restricted area.

"We've received many calls from tourism agencies and tourists," said Junichi Inayoshi, 46, who heads Aso's tourism association. "Mount Aso is a volcano with many safety measures in place so we want to assure them that it is safe to visit here."