The Prime Ministry Crisis Management Center said that flash floods in Istanbul and the neighboring province of Tekirdag killed 29 people.
Military helicopters hovered over districts on the European side of Turkey's largest city on Wednesday after two days of the heaviest rain in 80 years.
Prime Minister Tayyip Erdogan, a native of Istanbul, was due to travel to the city on Wednesday.
The center said in a statement posted in its web-site, "5 people in Saray town of Tekirdag and 24 others in Istanbul's districts of Catalca, Silivri and Ikitelli lost their lives in floods triggered by torrential rains on September 8 and 9."
"Efforts are under way to find two people in Tekirdag who were dragged away by flood waters. The Prime Ministry allocated an emergency fund of 250 thousand TL for Tekirdag and 2 million TL for Istanbul," it said.
"The flood waters swamped a number of houses and business places in Saray, Silivri, Catalca and Ikitelli. Some school buildings and state-run hospitals were also damaged. Search-and-rescue efforts as well as damage assessment works are under way in those worst-hit areas with the help of six helicopters and 35 boats," it said.
Rescue teams recovered bodies of three more people who died stranded in their vehicles due to flood, triggered by torrential rains, near Ikitelli truck parking area in Istanbul.
Truck drivers and staff of a truck parking area were dragged by flood, triggered by ongoing torrential rains, in Basaksehir, Istanbul.
Also, seven women who were dragged by flood when getting of a minivan in Bagcilar neighborhood lost their lives. Teams rescued three women who were also drifted away by flood.
Also, eleven people were stranded in a plantation area in Istanbul. Fire fighters and civil defense teams later rescued these people.
Body of one of the missing people was later discovered. Efforts are under way to find the other missing people and fire fighters have rescued four people by boats.
Also, efforts are under way to rescue three people who climbed to trees in the same area.
The trucks drifted by the flood blocked the highway towards Istanbul's Ataturk Airport on the European side.
Many vehicles on Ikitelli Basin Express highway were stranded due to torrential rains and flood. Some of the vehicles, and passengers in them, were dragged by flood.
Drivers and passengers are waiting for rescue teams, whereas fire fighters and civil defense teams are continuing their efforts with difficulties.
However, teams managed to rescue 50 people who were stranded in their vehicles in Ikitelli.
Also, gendarmery teams rescued 670 people in Silivri, and 314 others in Catalca.
The arteries around Ikitelli have been closed to traffic for security reasons.
Also, Ayamama, Tavukcu and Papaz brooks overflowed due to torrential rains, and one building in the vicinity of the brook demolished. Some factories were flooded in Yeni Bosna.
Istanbul's deputy governor Hikmet Cakmak said Ayazaga-Cendere highway was closed to traffic, and four military helicopters and eight boats joined rescue operations.
"Also teams in Silivri and Catalca are coming back to Istanbul," Cakmak said.
Cakmak said the number of rescue boats would be raised to 30 in an hour.
The deputy governor said flood occurred also around Bahcesehir Hamam Brook, and traffic was cut in the area.
Governor Guler said the two-day rain was equal to rain that generally fell in Istanbul in six months.
Northwestern town of Bandirma is another place hit by torrential rains and flood.
Workers were stranded at white meat manufacturing facilities in Bandirma, but helicopters and commandos from Bandirma Main Jet Base Command are rescuing them.
Highways connecting the town to Balikesir and Bursa provinces were closed to traffic due to flood.
Electricity is cut in the town, and authorities evacuated an apartment building as a precaution.
Ali Erdem, chief analyst in Istanbul Meteorology Deparment, told Reuters Tuesday's rainfall was the heaviest recorded in the last 80 years.