7.3 shock: An earthquake measuring 7.3 on the Richter scale jolted the southern part of West Java at 2:55 p.m. on Wednesday, 2 sep 2009. The tremor was felt as far as Jakarta and Yogyakarta in Central Java. (The Jakarrta Post)
A powerful earthquake caused buildings to sway in Indonesia's capital on Wednesday, damaging buildings and prompting a regional tsunami alert, witnesses and media said.
The quake struck at 2.55pm local time (1755 AEST) on the southern coast of the main island of Java with a preliminary magnitude of 7.4.
It had a depth of 63 kilometres and the epicentre was about 200 kilometres south of Jakarta, the US Geological Survey said.
The Pacific Tsunami Warning Centre said it was powerful enough to cause a local tsunami, but there were no immediate reports of high waves.
Buildings in Tasikmalaya, the town closest to the epicentre, were damaged, the Detik.com news portal reported.
There were no immediate reports of injuries.
The shaking was strong in the capital, Jakarta, where panicked office workers ran outside onto the streets.
It was not possible to immediately contact anyone in the quake area.