The Monday's 5.7 magnitude earthquake on Indonesia's Sumatra island helped prove that the newly-installed early warning siren in the West Sumatra provincial capital of Padang was functioning well, a report said Tuesday.

The roar was heard by the Padang inhabitants, and a local official even complained to the Padang Mayor that the siren was too loud, reported the national Antara news agency.

Padang and some other districts of West Sumatra were jolted by the earthquake at around 4:00 a.m. during the wee hours of Monday.

"The siren was roaring when the quake jolted the city, and the sound could be heard within a radius of three km," Padang Mayor Fauzi Bahar was quoted as saying.

Several hours after the quake, President Susilo Bambang Yudhoyono symbolically inaugurated the installation of the early warning devices in West Sumatra.

Fauzi said that if a subsequent tsunami occurs, evacuation of people must be completed within four hours.

West Sumatra installed six sirens under the local Meteorology and Geophysics Agency (BMG) as part of the tsunami early warning system. Such devices were also being constructed simultaneously in Bali and Aceh, where an earthquake-triggered tsunami unleashed a tsunami and killed over 131,000 people nearly two years ago.

The BMG has installed sirens on top of 15-meter towers in six coastal cities and districts facing the Indian Ocean -- Padang, Pesisir Selatan, Pariaman city, Padang Pariaman, Agam regency and West Pasaman.

Source: Xinhua