An earthquake registering magnitude 6.3 rocked a northern Indonesian island on Saturday as residents were ending their fast on the final day of the Muslim holy month of Ramadan, officials said. There were reports of at least two injuries but no tsunami warning was issued.

The U.S. Geological Survey said the late-afternoon quake struck 56 kilometers (35 miles) southeast of Palu city on Sulawesi Island at a depth of 19.9 kilometers (12.4 miles).

Sudirman, an officer at the Disaster Management Agency who uses one name, said there were reports from the province that at least two people were injured by falling debris and of damage to houses in Parigi Mountong, the district closest to the epicenter.

He said the full extent of the injuries and damage was not yet known.

The earthquake struck as people in the province were ending their fast on the last day of Ramadan, causing many to rush out into the streets in panic, local news reports said.

The USGS initially measured the quake at magnitude 6.6 but later adjusted it to 6.3.

Indonesia is prone to earthquakes because it is in the Pacific Ring of Fire, an arc of volcanos and fault lines encircling the Pacific Basin.

A giant quake off the country on Dec. 26, 2004, triggered a tsunami in the Indian Ocean that killed 230,000 people, half of them in Indonesia's westernmost province of Aceh.