Tribute to "Mbah" Maridjan on Facebook and Twitter

The system, which uses buoys to electronically detect sudden changes in water level, worked when it was completed, but by 2009 routine tests of it were showing problems, said the agency chief, who uses the single name Fauzi. By last month, he said, the entire system was broken because of  nexperienced operators.

“We do not have the expertise to monitor the buoys to function as intended,” he said.  As a result, he said, not a single siren sounded after Monday’s quake. It was unclear if any sirens could have made a difference, since the islands worst affected were so close to the epicenter that the tsunami would have reached them within minutes.

The group that set up the system, the Germany-Indonesia agency Tsunami Early Warning System (GITEWS), could not be reached for comment Wednesday, but the questions Fauzi raised highlighted the difficulty for a poor country such as Indonesia in disaster prevention and response.         On the ash-covered slopes of Mount Merapi, authorities continued a search for more victims. Dr. Teguh Dwi Santosa, who works at a local hospital, said the death toll had climbed to 30.  The eruption sent thousands streaming into makeshift emergency shelters, although the ash did not disrupt flights over Indonesia.

About 36,000 people have been evacuated, according to the Indonesian Red Cross. Some defied authorities and returned home to check on crops and possessions left behind. More than 11,000 people live on Merapi’s fertile slopes.

Tuesday’s blast eased pressure that had been building behind a lava dome on the crater. Experts warned that the dome could still collapse, causing an avalanche of the blistering gas and debris trapped beneath it.

“It’s a little calmer today,” said Surono, the chief of Center for Volcanology and Geological Hazard Mitigation. “But a lot of energy is pent up back there. There’s no telling what’s next.”

The volcano, whose name means “Fire Mountain,” has erupted many times in the last 200 years. In 1994, 60 people were killed, while in 1930 more than a dozen villages were incinerated, leaving up to 1,300 dead.

Among the dead from Tuesday’s eruption was an 83-year-old man named Maridjan, who was entrusted by a late king from the nearby city of Yogyakarta to watch over the mountain’s unpredictable spirits. He had refused to leave his house high on its slopes.

The discovery Wednesday of his ash-covered body, reportedly found in a position of Islamic prayer, kneeling face-down on the floor, rattled residents who for years joined his ceremonies to appease the rumbling giant by throwing rice, clothes and chickens into the crater.

Many Indonesians paid tribute to Maridjan on Facebook and Twitter.  “I’m more afraid than ever,” said Prapto Wiyono, a 60-year-old farmer from the mountain village of Pangukrejo. “Who’s going to tell us what’s going on with Merapi?”