Bulgaria's capital Sofia can safely endure an earthquake with a 7-9 magnitude, its chief architect said on Thursday in a bid to assuage fears as aftershocks continue to rattle homes and nerves.

A 5.9-magnitude earthquake struck Bulgaria's capital Sofia in the week hours last Tuesday, shaking apartment buildings, rattling windows and causing people to rush into the streets.

The chief architect has warned the jolt could have made casualties if it had hit in broad day light, due to fallen chimneys and roof tiles.

"We urgently should issue technical passports of the buildings and utility equipment in Sofia. Most of the buildings have their project documentation intact in the archives of the municipality or with the owners. If not, it must be issued again. This is like a preventive medical examination," Dikov told bTV channel.

Even though during the first seven-eight years after the fall of the communistic regime in 1989, no strict control over the construction quality in the city was exercised, Dikov claimed buildings were constructed to endure 7-magnitude jolts precisely in line with their respective project.