A strong earthquake with a magnitude of 6.2 has hit Istanbul and the surrounding regions, one of the strongest to strike the city of 16 million in recent years.

Buildings shook and crowds fled down busy streets as a quake in the Sea of Marmara rocked the major Turkish city and nearby communities.

Footage showed people running down a busy street to safety. The initial tremor reportedly lasted 30 seconds, before aftershocks hit.

A news reporter filming a live broadcast for CNN Turkey shook and gripped onto her desk as the earthquake was felt in Istanbul offices.

There were no immediate reports of damage, but people evacuated buildings as the quake hit and shook the city.

Broadcaster TGRT reported that one person had been injured as a result of jumping off a balcony during the quake, which occurred during a public holiday in Turkey.

People reported to have felt the quake as far away as Greece, North Macedonia, Romania and Bulgaria, with lower intensity. AFP journalists in Sofia said they had felt tremors.