The death toll has risen after a strong earthquake struck in the Aegean Sea between the Turkish coast and the Greek island of Samos, with officials saying least 26 people are dead and more than 800 have been injured.

The earthquake, which the Istanbul-based Kandilli Institute said had a magnitude of 6.9, was centred in the Aegean north-east of Samos, while Turkey’s Disaster and Emergency Management Presidency (AFAD) said it measured 6.6 and hit at a depth of some 10 miles.

The quake toppled buildings in Izmir, Turkey’s third largest city, and triggered a small tsunami in the district of Seferihisar and on Samos before being followed by hundreds of aftershocks.

Turkey Earthquake
The quake toppled at least eight buildings in Turkey’s third-largest city, Izmir (Emrah Gurel/AP)

Early on Saturday, onlookers cheered as rescuers lifted teenager Inci Okan out of the rubble of a devastated eight-floor apartment block.

Friends and relatives waited outside the building for news of loved ones still trapped inside, including employees of a dentist’s surgery that was located on the ground floor.

Two other women, aged 53 and 35, were rescued from another collapsed two-storey building.

At least 24 people were killed in Izmir, including an elderly woman who drowned, according to AFAD.

Two teenagers were killed on Samos after being struck by a collapsing wall.

Greece Earthquake
A collapsed wall led to the deaths of two teenagers on the Greek island of Samos (Michael Svarnias/AP)

At least 19 people were injured on the island, with two, including a 14-year-old, airlifted to Athens and seven taken to hospitals on the island, health authorities said.

It was felt across the eastern Greek islands and as far as Athens and in Bulgaria.

In Turkey, it shook the regions of Aegean and Marmara, including the country’s largest city Istanbul, whose governor said there were no reports of damage.

Turkey is crossed by fault lines and is prone to earthquakes. In 1999, two powerful quakes killed some 87,000 people in north-western Turkey.

Earthquakes are also frequent in Greece.

In a show of solidarity rare in recent months of tense bilateral relations, Greek and Turkish government officials issued mutual messages of solidarity while the countries’ presidents held a telephone conversation.