Dhaka, Nov. 22 -- When a 5.7-magnitude earthquake struck near Narsingdi just outside Dhaka on Friday morning, buildings cracked, stairwells filled with panic and at least 10 people died -- crushed by falling masonry, railings and walls, or as they tumbled from trees and upper floors.

For Prof Mehedi Ahmed Ansary, who teaches civil engineering at the Bangladesh University of Engineering and Technology (BUET), the damage from what was, in global terms, a moderate tremor is itself the message.

"What we saw today at magnitude 5.7. Imagine what happens at magnitude 7," he told bdnews24.com.

"Buildings will collapse, casualties will soar. If a major earthquake strikes within 100km of Dhaka, 200,000 to 300,000 people could be killed or injure...