At least 47 people have died after a terrifying magnitude ‌7.7 earthquake followed by a second 6.9 earthquake struck Indonesia, triggering a tsunami warning.

Residents reported tremors lasting about a minute, and there were also dozens of aftershocks striking fear into survivors.

“The quake was massive, the shock was so strong,” said Nona, a 51-year-old resident of Talibura, a village in East ‌Nusa Tenggara.

“There were 13 of us inside the house and we all ran to save ourselves.”

A house damaged in East Manggarai, East Nusa Tenggara province, Indonesia. Photo: AAP

The first quake struck around 5am on the island of Flores, destroying buildings.

Hours later, a second 6.9 earthquake struck Indonesia’s western Sumatra island late on Saturday.

After the terror of the earthquakes, there were fears that a follow-up tsunami could cause further devastation.

Warnings were issued, but tsunami waves of less than one metre were recorded in several parts of the Southeast Asian nation.

Authorities lifted a tsunami warning about three hours later.

Strong shaking was felt across East Nusa Tenggara, West ​Nusa Tenggara ​and parts of South Sulawesi, with residents in several ​areas reporting tremors lasting about a minute.

“Most of the people felt the shock and scattered ‌out of their homes,” said the National Disaster Mitigation Agency.

The road cracked open in Mbay, Nagekeo, East Nusa Tenggara Province, Indonesia. Photo: AAP

Indonesian geophysics agency recorded the first quake at a depth of 15km, followed by several aftershocks.

Indonesia straddles the Pacific Ring of Fire, ​a seismically active zone where tectonic plates meet, triggering frequent earthquakes and volcanic eruptions.

Australia’s tsunami warning centre said the undersea quake posed “no tsunami threat to the Australian mainland, islands or territories”.

Rescuers have been searching for people trapped in buildings and collecting bodies.

Twenty were found dead in the port town of Maumere, the main town in Sikka Regency on Flores Island in eastern Indonesia.

Residents remained trapped in ‌several buildings across the affected ⁠area, while there were reports of landslides blocking several roads.

Teams have yet to reach Nagekeo and mobile communications ​in the region were affected, Fathur told Reuters earlier.

Attempts to reach the area by road were thwarted by landslides, while another team was trying to reach it by ferry, he said.

About 2000 residents in Nagekeo evacuated, and damage was reported to homes, warehouses and government buildings, the National Disaster Mitigation Agency said.

Authorities also reported power outages and traffic congestion in parts of the regency.

East Nusa Tenggara Governor Emanuel Melkiades Laka Lena told a press conference that at least five people were killed when buildings collapsed as they slept.

Preliminary data ⁠showed 157 homes were heavily damaged, 41 moderately damaged and 148 lightly damaged.

Damage was also reported ‌at 87 schools, 18 ​health facilities, five places of worship and six office buildings, along with other infrastructure.

Parts of a building collapsed into dust and rubble as people screamed and ran in the street, ​according to a ‌Facebook video, verified by Reuters as being filmed at a port in Maumere.

Rescuers were searching for survivors beneath a partially collapsed port building.

Siti Sulfia Bira, 37, who lives ​with her family near the port in Maumere, said she rushed to higher ground when the tremors started.

“At the moment we don’t dare to go home just yet because the situation isn’t stable; we still worry that there might be more tremors coming,” she told Reuters.

A hospital in Ende district in East Nusa Tenggara was moving patients outside, Kompas TV footage showed, while Kompas.com reported at least one landslide.

-with AAP