A magnitude 5.6 quake triggered alarm sirens after it struck Indonesia on Monday afternoon. Footage shows the locals gathering in a courtyard to take shelter as a shrill alarm rang throughout the Kalibata area of South Jakarta on November 21.The United States Geological Survey said the tremors struck 18 kilometres west-southwest of the Ciranhang-hilir region at a depth of 10 kilometres at 1:21 pm local time.Indonesia's Meteorology, Climatology, and Geophysics Agency urged residents to watch out for aftershocks, but said the tremor did not trigger a tsunami warning.There were no immediate reports of injuries or casualties.