A French rescue team has detected a person believed to be alive trapped under rubble in an earthquake-hit Indonesian city.

Relief workers said they had located the individual in Palu, six days after the area was badly affected by a powerful 7.5-magnitude tremor and subsequent tsunami.

Philip Besson, a member of the French organisation Pompiers de l'urgence, said the team “detected the presence of a victim” in the wreckage of the city’s Mercure Hotel.

However, he added rescuers had been unable to determine whether or not the person underneath the rubble is conscious.

Indonesian earthquake: rescue efforts continue Show all 30 1 /30 Indonesian earthquake: rescue efforts continue Indonesian earthquake: rescue efforts continue Residents and rescuers walk in front of a washed out passenger ferry in Wani following the September 28 earthquake and tsunami. Aid poured into disaster-ravaged Palu after days of delays as efforts ramped up to reach 200,000 people in desperate need AFP/Getty Indonesian earthquake: rescue efforts continue Indonesian rescuers try to free a 15-year-old earthquake survivor, Nurul Istikhomah from the flooded ruins of a collapsed house in Palu EPA Indonesian earthquake: rescue efforts continue A rescue team searches for bodies under the ruin of a house in Balaroa EPA Indonesian earthquake: rescue efforts continue A ship stranded on the shore EPA Indonesian earthquake: rescue efforts continue Indonesians stand among debris at Mamboro village in Palu EPA Indonesian earthquake: rescue efforts continue Residents carry a victim AFP/Getty Indonesian earthquake: rescue efforts continue Residents trying to salvage belongings from their homes which collapsed AFP/Getty Indonesian earthquake: rescue efforts continue Indonesian soldiers bury quake victims in a mass grave in Poboya AFP/Getty Indonesian earthquake: rescue efforts continue A damaged mosque AFP/Getty Indonesian earthquake: rescue efforts continue A man sits on the rubble of a house AFP/Getty Images Indonesian earthquake: rescue efforts continue Rescuers walk past debris AFP/Getty Images Indonesian earthquake: rescue efforts continue Jumadil, 5, reacts at seeing his mother Susi Rahmatia, 26, after he went missing for seven days AFP/Getty Images Indonesian earthquake: rescue efforts continue A woman builds a temporary toilet AFP/Getty Images Indonesian earthquake: rescue efforts continue Rahmat Raidi, 26, shows portraits of his missing family members AFP/Getty Images Indonesian earthquake: rescue efforts continue Residents queue before receiving humanitarian aid in Palu AFP/Getty Images Indonesian earthquake: rescue efforts continue Indonesian villagers offload aid from a military helicopter in Proo village, Lindu district AFP/Getty Images Indonesian earthquake: rescue efforts continue Residents stand among houses destroyed by a landslide that was triggered by the earthquake in Petobo outside Palu EPA Indonesian earthquake: rescue efforts continue People queue for fuel at a petrol station in Palu Reuters Indonesian earthquake: rescue efforts continue Members of the Indonesian Red Cross attend to a victim at a crushed house at Talise beach in Palu EPA Indonesian earthquake: rescue efforts continue Residents walk among houses destroyed by a landslide that was triggered by the earthquake in Petobo, outside Palu EPA Indonesian earthquake: rescue efforts continue An Indonesian Police Officer uses a dog to search for victims amongst rubble in Petobo, outside Palu Reuters Indonesian earthquake: rescue efforts continue An Indonesian rescue team searches for victims and survivors amongst the rubble of the Roa Roa hotel in Palu Reuters Indonesian earthquake: rescue efforts continue A crowd gathers at the airport in Palu in the hope of fleeing by plane Getty Indonesian earthquake: rescue efforts continue Members of an Indonesian rescue team look for survivors in a collapsed home in Palu AFP/Getty Indonesian earthquake: rescue efforts continue Bhayangkara hospital in Palu Reuters Indonesian earthquake: rescue efforts continue Members of an Indonesian rescue team look for survivors in a collapsed home in Palu AFP/Getty Indonesian earthquake: rescue efforts continue An earthquake damaged bridge in Palu Reuters Indonesian earthquake: rescue efforts continue People drive amongst the damage in Palu Reuters Indonesian earthquake: rescue efforts continue Indonesian women stand on a tsunami devastated area of Talise beach Palu EPA Indonesian earthquake: rescue efforts continue Members of an Indonesian rescue team look for survivors in a collapsed home in Palu AFP/Getty

Mr Besson said the team could not yet reach the victim, who was trapped under thick concrete. The team only had a hand drill and stopped digging as night fell.

Rescuers will return to the scene with heavy equipment early Friday to make a fresh attempt to rescue the person.

Some 1,200 people, mainly from Palu, are confirmed dead after the quake hit the island of Sulawesi last week, while hundreds of others are still unaccounted for.

Thousands of buildings were reduced to rubble by the disaster, leaving authorities fearful the bodies of many more victims could lay beneath the debris.

British aid agencies have been among the international organisations to provide support as much-needed supplies slowly begin to reach the disaster zone.

The eruption of volcano Mount Soputan in North Sulawesi this week has hampered relief efforts by sending an ash cloud spewing nearly 20,000ft into the sky.

International development secretary Penny Mordaunt said that thousands of shelter kits, solar lanterns and water purifiers were sent from the UK to Indonesia on Thursday.

A team of six UK humanitarian experts left London for Sulawesi earlier this week, and are now helping to coordinate the humanitarian response on the ground.

However, aid workers have reported widespread food shortages in Palu, as well as fears difficulties transporting supplies to affected areas could result in more casualties.