Cilacap (Indonesia): Hundreds of residents fled an Indonesian port town for higher ground on Monday when an earthquake struck south of Java with a magnitude of 6.7 as estimated by US seismologists.

The US Geological Survey said that the epicenter in the Indian Ocean was 24 km miles deep, after initially estimating it at 10 km underground and 277 kilometres south of the Javanese coast.

Indonesian seismologists put the magnitude at 7.1 and issued a tsunami warning, saying the tremor had the potential to cause a killer wave and asking recipients of SMS to warn others of the danger.

The warning was later cancelled. When the quake struck hundreds of residents in the seaport town of Cilacap fled inland car.

"They were all panicking and shouting 'quake, quake'," the reporter said. Suharjono, the technical head of Indonesia's Meteorology and Geophysics Agency, said shaking from the tremor had been felt in Pangandaran and Cilacap districts in Java.

The US Pacific Tsunami Warning Centre had said that there was no risk of a widespread destructive wave, but there was a "very small possibility of a local tsunami".

The earthquake epicenter was 241 km from the remote Australian territory of Christmas Island, and seismologists said the tremor was felt there, but no tsunami warning alert was issued for Australia.