Rescuers are searching through the rubble of a partially-collapsed Indonesian hospital after an earthquake struck the island of Sulawesi, leaving at least 30 dead. The 6.2-magnitude quake on Friday morning came just hours after an earlier, smaller tremor. Hundreds of people were injured and thousands displaced by the quake. Indonesia has a history of devastating earthquakes and tsunamis with more than 2,000 killed in a 2018 Sulawesi quake. Local media have reported that six patients and their families were trapped when parts of the Mitra Manakarra hospital in the town of Mamuju collapsed. Arianto, from the rescue agency in Mamuju city, told news agency AFP they were trying to reach those trapped. He did not specify a number. Authorities have put the overall death toll for the city at least 26 but fear that more are buried under collapsed buildings, the agency said. The epicentre of Fridays quake was six kilometres (3.73 miles) northeast of Majene city at a depth of 10km. The initial toll for Majene was reported as four people killed and hundreds injured. The situation was pretty bad, Dr Gayatri Marliyani, of the geology department at Gajah Mada University in Yogyakarta, told the BBC. She said the governors office was among the collapsed buildings and confirmed that several hospitals and one hotel had also been damaged. She also warned that getting response teams to the area could be hampered by the coronavirus pandemic. Tremors were felt at around 01:00 local time on Friday (17:00 Thursday GMT) for about seven seconds. No tsunami warning was issued but thousands are reported to have left their homes, fleeing to safety. Authorities have warned that strong aftershocks could follow the two main quakes and that they could still trigger a tsunami. Indonesia is prone to earthquakes because it lies on the so-called Ring of Fire - a line of frequent quakes and volcanic eruptions on the Pacific rim. In 2004, a tsunami triggered by an earthquake off the Indonesian island of Sumatra killed 226,000 people across the Indian Ocean, including more than 120,000 in Indonesia. The Indian Ocean tsunami of 2004 killed 170,000 people on the Indonesian island of Sumatra after a quake of magnitude 9.1.