Jakarta, Indonesia (CNN) -- The death toll from recent eruptions of Indonesia's Mount Merapi volcano climbed to 259 on Monday, government officials said.
The toll keeps rising as rescuers search for victims, the National Disaster Management Agency said.
"Five hundred and eleven people suffered from severe burns and are now being treated in the hospital," said Haartje Robert Winerungan of the National Disaster Management Agency.
The government's volcano alert level remains at its highest level.
On Monday, volcanic activity included 12 earthquakes, 14 avalanches and continual tremors, according to the Center for Volcanology and Geological Hazard Mitigation. There also have been signs of continuing eruption over the past few days.
Merapi continued to shoot ashy, white smoke as high as 1,300 meters [4,265 feet], and hot ash rain was reported in a region close to the volcano.
Mount Merapi started its recent eruptions on October 26.
The volcano has since displaced nearly 400,000 people, according to the Disaster Management Agency.
On Thursday, officials said that the worst might be over. By Monday in several areas, the government had reduced the danger zone to a 10- or 15-kilometer [6.2-mile to 9.3-mile] radius of the volcano, scaling back from the previous 20 kilometers.
Disaster officials have expanded and reduced the danger zone in various areas, depending on volcanic activity over the past several weeks. That has caused some confusion.
"Thousands of refugees have ignored the danger-zone warning and returned to their villages since Sunday," Sutopo Nugroho, director of disaster risk reduction from the national coordinating board, said on Monday.
"Most of them were confused, because the safe zone in some areas have been reduced. We are sending teams to persuade these people to come back and put signs at the danger area to help prevent any more casualties."
Merapi, which looms on the horizon north of the major city of Yogyakarta, is on the island of Java.
U.S. President Barack Obama was forced to cut short his visit to Indonesia last week because of the volcano's ash cloud.
President Susilo Bambang Yudhoyono has called the volcanic eruptions a crisis situation. He and several ministers have visited the area and taken part in relief efforts.
The volcano has a summit elevation of almost 3,000 meters (10,000 feet). It is one of Indonesia's most active volcanoes and lies in one of the world's most densely populated areas. Many people raise crops and livestock in its shadow.
Yudhoyono has announced that residents will receive compensation for livelihoods and animals lost to the eruptions. The government will buy endangered cows on the volcano, the president said.
Many of those who live on its slopes risked their lives by staying or returning to feed their cows during lulls in the volcanic activity.
About 1,300 people died when the volcano erupted in 1930.
CNN's Andy Saputra and journalist Masyitha Baziad contributed to this report.