A picture taken at sunset on August 17, 2017 shows a view of Sultanahmet mosque (aka the Blue mosque) in the historic Sultanahmet district of Istanbul. (AFP PHOTO)

ISTANBUL, Aug. 17 (Xinhua) -- An earthquake larger than magnitude 7 is expected to hit Turkey's Marmara region in the near future, Bogazici University's Kandilli Observatory said Thursday.

"All the scientists have admitted that fact," Haluk Ozener, head of the Observatory, said at a press conference in Istanbul marking the 18th anniversary of a big earthquake that killed around 18,000 in northwestern Turkey.

"We can detect possible magnitudes and possible locations of future earthquakes but due to today's technology we cannot know their specific dates," Ozener said, adding that the expected quake would be a one-piece or two-piece fracture.

"The only thing that can be done is to reduce earthquake damage," he noted.

The earthquake in 1999 hit Turkey's most industrial and densely populated Marmara region with a magnitude of 7.8, according to Kandilli Observatory.

A recent statement by the Union of Architects and Engineers of Turkey shows most of the buildings in Istanbul, Marmara's largest city, are still not safe with the potential risk of collapse in a quake, local media reported.