(CNN) -- At least two people were killed after four earthquakes struck within an hour's time near the northern coast of Papua, Indonesia, midday Wednesday, authorities said. A fifth and sixth quake hit the region a few hours later.
"Two people dead, 20 houses collapsed" on the island of Yapen, according to Papua police spokesman Wachyono, who goes by a single name. There were also reports of fires burning, he added.
A 6.4 magnitude quake quake struck at 12:06 p.m. local time, followed by a more powerful 7.0 magnitude quake 10 minutes later, the U.S. Geological Survey reported. Within the next 42 minutes, a 5.1 magnitude quake also rattled the region, along with a magnitude 6.2 quake. Weaker quakes of magnitude 4.9 and 4.8 hit the area after 3 p.m.
The epicenters of the earthquakes were clustered within 90 kilometers (56 miles) of each other and some 180 kilometers (110 miles) north of Enarotali, Indonesia.
"People ran out of their houses and headed for higher ground in fear of a tsunami," said Denni Siregar, the police chief of Yapen Island sector, which lies near the epicenters. "There's no injuries reported yet but at least one house is damaged."
A tsunami watch that was issued by the Indonesian Meteorological Agency was later lifted.
Indonesia is on the so-called Ring of Fire, an arc of fault lines circling the Pacific Basin that is prone to frequent earthquakes and volcanic eruptions.
In 2004, a 9.1-magnitude underwater earthquake struck off the coast of Sumatra, triggering a tsunami that killed more than 200,000 people in 14 countries.
The tsunami, which washed away entire communities, caused nearly $10 billion in damage and more casualties than any other tsunami in history, according to the United Nations. Indonesia was among the hardest hit nations.