Four days after a 7.5 magnitude quake hit its Central Sulawesi region triggering a tsunami and killing more than 800 people, bodies of dozens of students have been pulled out of a landslide-swamped church in Sulawesi, officials said Tuesday, as an international effort to help nearly 200,000 Indonesia quake-tsunami victims ground into gear. The Indonesia quake toll is expected to go up manifolds.

Meanwhile, an earthquake measuring 6.0 on the Richter scale rocked Sumba island of Indonesia on Tuesday.

At least 844 people are already known to have died, but officials say the number is certain to rise — perhaps into thousands — as isolated communities are reached and the scale of the disaster becomes clearer.

Survivors are battling thirst and hunger, with food and clean water in short supply, and local hospitals are overwhelmed by the number of injured. Rescue efforts have been hampered by a lack of heavy machinery, severed transport links and the scale of the damage.

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The grim discovery at the Central Sulawesi church was made by the Red Cross.

“A total of 34 bodies were found by the team,” Indonesia Red Cross spokeswoman Aulia Arriani told AFP, adding that 86 students had initially been reported missing from a Bible camp at the Jonooge Church Training Centre. Arriani said rescuers faced an arduous trek to reach the mudslide and retrieve the victims.

“The most challenging problem is travelling in the mud as much as 1.5 hours by foot while carrying the bodies to an ambulance,” she said.

The United Nations Office for the Coordination of Humanitarian Affairs warned Monday that there were 191,000 people in urgent need of help after the quake-tsunami, among them 46,000 children and 14,000 elderly — many in areas that aren’t the focus of government recovery efforts.

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The dead — many yet uncounted, their bodies still trapped in the rubble of collapsed buildings — are also a source of concern for authorities.

At Poboya — in the hills above the devastated seaside city of Palu — volunteers are filling a vast grave with the dead, with instructions to prepare for 1,300 victims to be laid to rest.

Many survivors have spent the last couple of days desperately searching for loved ones while dealing with the trauma of the disaster.

The desperate among them have turned to looting shops for basics like food, water and fuel as police look on, unwilling or unable to intervene.

“The government, the President have come here, but what we really need is food and water.” Burhanuddin Aid Masse, 48, told AFP.

Meanwhile, at Sumba island, no tsunami alert was issued after Tuesday’s earthquake, and there was no report of damages so far, an official said.

The meteorology and geophysics agency said the quake hit at 7.16 am at a depth of 10 km under the seabed with its epicentre 66 km southwest Sumba Timur.

Indonesia sits on a vulnerable quake-stricken areas called the Pacific Ring of Fire, making it prone to earthquakes.