Guwahati/Aizawl, Jul 19 (IANS): A moderate intensity earthquake measuring 4.2 on the Richter scale hit southern Assam's Hailakandi district on Saturday, taking the number of tremors felt by the northeastern states to 14 in 18 days, officials of the India Meteorological Department (IMD) said. No damage was reported.

Fresh tremors were felt in Hailakandi district and in adjoining areas of Assam at 4.25 p.m., the officials added.

The IMD officials said that the epicentre of the tremor, that lasted a few seconds, was at 63 km depths.

Of the 18 earthquakes, five took place in Mizoram followed by four in Assam, three in Meghalaya and one each in Arunachal Pradesh and Nagaland.

With a population of 1.1 million, Mizoram, the second least populous state in the country, has recorded successive quakes since June 22, when a moderate earthquake, measuring 5.5 on the Richter Scale, shook the Champhai district and adjoining areas, damaging more than 31 structures, including roads, buildings and important installations.

Besides Champhai, a series of tremors also hit Saitual and Serchhip districts since June 22.

Seismologists consider the mountainous northeast region as the sixth major earthquake-prone belt in the world.

The northeast region of India has seen some of the biggest quakes in history. In 1897, a Shillong-epicentre quake measuring 8.2 on the Richter scale had hit the area. In 1950, an earthquake measuring 8.7 on the Richter scale had altered the course of the Brahmaputra river.