The earthquake, late on Sunday, struck out at sea at a depth of 36km with several smaller aftershocks, geophysics agency Meteorological, Geophysical and Climatological Agency (BMKG) said.
“The tsunami early warning has ended,” the BMKG said in a statement.
Tremors shook buildings, alarming residents of some cities, and authorities urged people to move to higher ground.
“The quake was felt quite strongly and with an intensity that lasted quite long,” Yusuf Latif, a spokesman for the search and rescue agency, told Reuters.
“There were no reports of damage or casualties in Ternate,” he added, referring to the city closest to the epicentre.
The US Geological Survey had earlier said the earthquake was centred 185km southeast of Manado at a depth of 24km.
The quake caused panic in the city of Ternate in the Maluku islands chain, where people ran to higher ground.
Local media reported some hospitals in Ternate, about 130km from the epicentre, suffered minor damage and had to evacuate patients.
#BREAKING NEWS: Indonesian authorities have issued a TSUNAMI WARNING after a magnitude 6.9 earthquake in the Molucca Sea 80 miles SW of Ternate City Indonesia. AP News reporting people heading into the hills for safety. #Tsunami #Indonesian #Earthquake pic.twitter.com/qoH2rnN9ls
— The Weather Channel (@weatherchannel) July 7, 2019
“I was getting ready to sleep when the window started rattling,” Budi Nurgianto, a Ternate resident, told AFP news agency.
“It was very strong. I ran from my house and all my neighbours fled too.”
Strong tremors were felt for a few seconds in the nearby seaside resort city of Manado, residents said, but no damage was reported.
Indonesia is one of the most disaster-hit nations due to its position straddling the so-called Pacific Ring of Fire, where tectonic plates collide.
It has been hit by a string of deadly earthquakes, including a devastating one in 2004 measuring 9.1 that struck off the coast of Sumatra and triggered a tsunami that killed 220,000 throughout the region, including 168,000 in Indonesia alone.
The Boxing Day disaster was the world’s third-biggest earthquake since 1900, and lifted the ocean floor in some places by 15 metres.
Indonesia’s Aceh province is the hardest hit area, but the tsunami affects coastal areas as far away as Africa.
Last year, a magnitude 7.5 earthquake and a subsequent tsunami in Palu on Sulawesi Island killed more than 2,200 with about 1,000 others declared missing.