Guwahati/Kolkata/Thimpu, Sep 21 - An earthquake measuring 6.3 on the Richter scale rocked parts of Assam, other north-eastern states of India, West Bengal and neighbouring Bhutan Monday afternoon causing damage to various properties in both the countries.

The tremors were felt at 2.26 p.m. No casualties were reported.

The epicentre was plotted in Munggar in Bhutan. Munggar, about 500 km from Thimpu, is located along the India-Bhutan border, 125 km northwest of Guwahati.

Preliminary reports say cracks developed in apartments and concrete structures in Guwahati.

This is the fifth and the highest intensity earthquake to have rocked the northeast since Aug 13, according to the Regional Seismological Centre of Shillong.

The tremors were also felt in parts of West Bengal, including state capital Kolkata.