An earthquake measuring 5.4 on the Richter scale rocked Kolaka district, Southeast Sulawesi, on Monday evening, prompting local people to rush outdoors. The epicenter of the quake which struck at 04.53 local time was on land 87 km from the Southeast Sulawesi provincial capital of Kendari at a depth of 21 km, ANTARA quoted Head of the Pomalaa Meteorology, Climatology and Geophysics Office Agus Suprianto as saying today. The quake which lasted for three seconds also forced the evacuation of patients being treated at the Kolaka regional general hospital to the hospital\'s yard for fear of unexpected thing. A number of houses cracked and a house on Jalan Pemuda in Kolaka collapsed. Until Monday evening, many panic-stricken people were staying outdoors as a number of aftershocks of lower intensity still occurred. The local geophysics office recorded at least eight aftershocks after the 5.4-magnitude quake rattled the area. No fatalities or injuries were reported in the quake. Indonesia sits on the Pacific \"Ring of Fire\" where the meeting of continental plates causes high volcanic and seismic activity.