ISTANBUL/ATHENS/SOFIA - At least nine people were killed on Tuesday as flash floods hit Turkey, Greece and Bulgaria.

Two died in Istanbul, where the city's streets turned into fast flowing rivers.

About a dozen people were rescued after being stranded inside a library, while some subway stations were shut down.

Istanbul governor Davut Gul urged motorcyclists to stay home.

Elsewhere in the country, Turkish Interior Minister Ali Yerlikaya said four other people were missing after the flash flood swept over the campsite in Kirklareli province, near the border with Bulgaria.

Mr Yerlikaya said about 12 campers were at the site when the waters hit.

Search teams had located two bodies, he said on X, the social media platform formerly known as Twitter. “The search and rescue efforts for the missing (four) continue uninterrupted,” he said.

Television footage showed rescuers carrying a young girl and an adult to safety from waters reaching waist-high in some areas. The rains also damaged and forced the closure of a main road, HaberTurk television reported.

Heavy rain also hit neighbouring Greece and Bulgaria causing floods that killed at least five people.

In Greece, police banned traffic in the central town of Volos, the nearby mountain region of Pilion and the resort island of Skiathos as record rainfall caused at least one death, channelled thigh-high torrents through streets and swept cars away.

The fire department said one man was killed near Volos when a wall buckled and fell on him.

At least five people were reported missing, possibly swept away by floodwaters.

Authorities sent text message alerts in several other areas of central Greece, the Sporades island chain and the island of Evia warning people to limit their movements outdoors.

Streams overflowed their banks and swept cars into the sea in the Pilion area, while rockfalls blocked roads, a small bridge was carried away and many areas suffered electricity cuts. Authorities evacuated a retirement home in the city of Volos as a precaution.

Greece’s weather service said one Pilion region village received 75.4cm of rain late on Tuesday, by far the highest level recorded since at least 2006.

The average annual rainfall in the Athens region is around 40cm, it said.

Heavy rain is expected to ease after noon on Wednesday, said Vassilis Kikilias, Greece's Minister of Climate Change and Civil Protection.

People in impacted areas are advised to stay in doors.