Workers cleaned up damaged buildings after the deluge while rescuers deployed a thermal drone to help the search, using excavators and their bare hands to try to find survivors in the rivers and rubble.

Torrential rain on Saturday evening triggered flash floods, landslides, and cold lava flow, a mud-like mixture of volcanic ash, rock debris and water, in three districts in West Sumatra province. On Monday, the death toll was 43.

Authorities said four suspects, including an Indonesian national, were arrested earlier this month at a villa on the island.

Hours of heavy rain caused large volcanic rocks to roll down one of Indonesia's most active volcanos into two districts in the province Saturday evening, while flooding inundated roads, homes and mosques.

The Meteorology, Climatology and Geophysics Agency (BMKG) said the recent heavy rainfall in the province was related to abnormally warm sea surface temperatures producing moisture-laden clouds.

No damage or casualties were immediately reported but images showed a column of ash soaring into the sky on Halmahera island in North Maluku.

Hours of heavy rain caused flooding in two districts in West Sumatra province on Saturday evening and sent sweeping ash and large rocks down Mount Marapi, the most active volcano in Sumatra.

The disaster hit Agam and Tanah Datar districts in West Sumatra province at around 10:30 pm (1530 GMT) on Saturday after hours of heavy rain, triggering a flash flood and a cold lava flow from Mount Marapi, according to the National Search and Rescue Agency (Basarnas).

The bus was carrying more than 60 students and teachers from Depok to Lembang, a popular tourist spot, when it crashed at 6:48 pm (1148 GMT) on Saturday.

In a speech at the National Development Planning Conference (Musrenbangnas), outgoing President Joko “Jokowi” Widodo once again called on regional administrations to fall in line with the central government’s policies and priorities.

Police are working to arrest a group of local residents who allegedly attacked officers and damaged a police vehicle while freeing a drug suspect during a raid on Jl. Pelita V.

More than 100 people were evacuated to mosques or relatives' homes and more than 1,300 families were affected with authorities trying to evacuate them.

About 9,800 people live on Ruang island, in the province of North Sulawesi, but in recent weeks all residents have been forced to evacuate after the mountain has continued to spew incandescent lava and columns of ash kilometres into the sky. 

Authorities this week raised the alert status of the volcano to the highest level, closed the provincial airport in Manado, and also warned of a possible tsunami if parts of the mountain collapse into the surrounding waters.

Antelmus' zinc-roofed house, about 7 kms (4.35 miles) from the 725-metre (2378.61 ft) high volcano, was heavily damaged by the ejected material.

Authorities are evacuating thousands more residents living near Mount Ruang in North Sulawesi after it erupted for a second time in a month, with officials planning to permanently empty out two villages at the foot of the volcano.

Mount Ruang erupted three times on Tuesday, spewing lava and ash more than five kilometres (three miles) into the sky and forcing authorities to issue evacuation orders for 12,000 locals.

The country's Center for Volcanology and Geological Hazard Mitigation (PVMBG) raised the alert level to the highest following the morning eruption, urging residents not to get near the volcano, according to its website.

The foreigners had held unlicensed shooting for a reality TV show involving 31 Korean nationals and one Indonesian national.

While no aftershocks were forecast after the main earthquake on Saturday night, authorities warned people to check on building conditions before returning to their homes, and to stay alert for landslides and flash floods that could be triggered by heavy rain in some parts of the quake-affected area. 

Mount Ibu, located on the island of Halmahera, erupted at 12:37 am (1537 GMT Saturday) and sent a thick column of dark smoke and ash west of the peak. 

The quake, which the United States Geological Survey recorded at a magnitude of 6.1, was felt in capital Jakarta -- where people were forced to evacuate buildings -- and in nearby Bandung, West Java.

Heightened volcanic activities in several regions across the archipelago have prompted residents to remain vigilant, as a number of eruptions have caused fatalities and forced thousands to flee their homes for safety.

Scientists are in a race against time to conserve East Java's endemic green orchid, which is marked "endangered" on the IUCN Red List and grows only in the province's lowland teak forests.

Collisions between trains and road vehicles on railway level crossings continue to occur with many analysts pointing to a disregard for safety that has remained unchanged over the years.

Former North Sumatra governor Edy Rahmayadi is looking to gain support from the PDI-P in his bid to return to the position of North Sumatra governor.

Shootouts between the Indonesian Military (TNI) and rebel groups continue despite mounting calls for security forces to apply a different approach to curb conflict in the region.

Officials had warned the threat from the Mount Ruang stratovolcano was far from over after it sparked the evacuation of thousands when it stirred a spectacular mix of lava, ash columns and lightning last week.

With just under four months to go until the country celebrates its 79th anniversary, the government is finalizing its plans and preparations to relocate almost 12,000 civil servants to the new capital still under development in East Kalimantan.

The national volcanic center and disaster agency have called for increased vigilance among people living near active volcanoes, especially those designated either orange or yellow alert, as security forces assist in evacuations and delivering aid to people affected by Mount Ruang, which has been on red alert since April 17.