Pakistan's Karachi hit by torrential rain and floods

Pakistan declared a public holiday in Karachi on Wednesday as the financial capital braced for more rain, after the arrival of the annual monsoon season left at least 7 people dead and caused widespread flooding, officials said.

The monsoon has brought havoc across Pakistan in recent days with the death toll from flash floods that struck the mountainous northwest on Friday rising to 377.

In Karachi, at least seven people have died since the rains began in the southern port city on Tuesday, said Abdul Wahid Halepoto, a provincial government spokesperson. Rainfall reached levels not seen in years in some parts of the city, Pakistan's largest, with a population of more than 20 million.

A bus drives through a flooded road after heavy rainfall in Karachi, Pakistan, on Tuesday. AP

Authorities ordered educational institutions and offices to shut.

"We are expecting more intense rains," said Anjum Nazir, a spokesperson for the provincial meteorological department.

Tuesday's rain was recorded between 80 mm (3.15 inches) and 178 mm (7.01 inches) in different parts of the city, he said.

A man takes shelter as a car lies partially submerged in floodwaters along a street after heavy rainfall in Karachi on Tuesday. AFP

Nazir said the area around the airport received 163.5 mm of rain, the highest recorded there since 1979. Some 178mm of rain was recorded in the northeast of the city, the highest since the weather station there was set up five years ago.

The rain also disrupted power, mobile phone services and flights, officials said. Local television footage showed cars and other vehicles floating down streets, with houses submerged in water.

Rescue workers, police, volunteers and government civic agencies were helping relief efforts, the city's Mayor Murtaza Wahab told local Geo News television.

Passengers disembark from an auto rickshaw that got stranded on a flooded road after heavy monsoon rains in Karachi on Wednesday. AFP

"We have all our resources at work," he said.

Wahab said the rain had overwhelmed the city's infrastructure.

There have also been heavy monsoon rains in Mumbai, India's financial capital, with some parts of the city drenched with as much as 875.1 mm of rain in the five days leading up to August 20, the local weather department said.

Many schools in the city were closed for a second straight day on Wednesday, while train services were disrupted.

Authorities requested residents avoid venturing out as more rain was predicted.

Reuters