People in the national capital region were jolted out of sleep early on Tuesday after four slight-intensity quakes were felt within a span of three hours. The first tremor of 3.1 magnitude on the Richter Scale occurred at 12:41 am followed by the second earthquake of 3.3 magnitude at around 1.41 am. Hundreds of panicked people in Delhi and adjoining cities of Gurgaon, Noida and Ghaziabad rushed out of their homes after the first quake and most were still out in the open when tremors were felt for the second time.Later two more quakes of 2.5 and 2.8 magnitude intensity followed at 1.55 and 3.40 am respectively. The tremors lasted for three to four seconds. While the epicenter of the first quake was at a depth of 10 kilometers below the ground near Sainik Farms area in South Delhi, the second was centered south-east of Manesar near Gurgaon in Haryana. Its well known that Delhi lies in seismic zone 4.