FRENCH rescuers have been unable to find the possible sign of life they detected a day earlier under hotel rubble in Indonesia’s central Sulawesi, a week after a destructive earthquake and tsunami struck the island.

The five-member International Emergency Firefighters team said late on Thursday its sensor “detected the presence of a victim” under thick concrete in the wreckage of the Mercure Hotel in Palu city.

The device can identify breathing and heartbeats, but gas leaks and other factors can result in false positives.

The team stopped digging overnight. But after an hour of searching on Friday morning, team member Philip Besson said they could not find the signal again.

“We are perplexed and frustrated mostly. We strongly believed in it yesterday. Now we have nothing at all... we tried everything and have no response,” he said.

Local rescuers were continuing to dig at the collapsed hotel. The French rescuers said on their Facebook page that 40 people including six workers are missing from the hotel. The death toll from Friday’s 7.5 magnitude earthquake that spawned a tsunami has risen to 1558, with scores more believed buried in deep mud and under debris of collapsed buildings and homes.

The national disaster agency said the body of a South Korean man was among eight dead pulled on Thursday from the wreckage of another hotel in Palu, the Roa Roa, which collapsed sideways in a heap of cement and steel.

Local television said the man, the only foreigner known to have died in the disaster, was a paraglider taking part in an event in the area.

Thousands have been injured and more than 70,000 evacuated to shelters and makeshift tents that have sprouted across Palu, the provincial capital of Sulawesi island that is home to most of the victims, and its surrounding areas.

Military transport planes from Australia, India, Singapore, Malaysia and elsewhere have landed with relief goods. Officials have listed tents or shelter kits, water treatment, electric generators and medical supplies as immediate needs.