Villagers move to safety from a flooded village near Nowshera, in Pakistan's Khyber-Pakhtoonkhwa province, on Thursday. (Mohammad Sajjad/Associated Press)

Massive flooding in Pakistan has killed at least 430 people as monsoon rains continue to bloat rivers, submerge villages and trigger landslides, according to rescue and government officials.

At least 291 people have died in Khyber-Pakhtunkhwa province, in the country's northwest, since Wednesday, said Mujahid Khan of the Edhi Foundation, a privately run rescue service that operates morgues and ambulances across the South Asian country.

Provincial officials called the flooding the worst in 90 years.

Residents and shopkeepers wade through a flooded street with their belongings after heavy rains in Peshawar, in northwest Pakistan, on Thursday. (Fayaz Aziz/Reuters)

Pakistan's poor infrastructure has been unable to stand up to the terrible weather.

Under-equipped rescue workers have struggled to reach up to 400,000 stranded villagers, while the highway connecting Peshawar to the capital city Islamabad had to be shut down.

There are also only 48 boats available for rescue.

Pakistani TV showed striking images of people clinging to fences and other stationary items as water at times gushed over their heads.

In Pakistani-controlled Kashmir, at least 22 people had been confirmed dead as of Thursday evening, the area's prime minister, Sardar Attique Khan, told reporters.

The death toll from the deluge was expected to rise because many people were still missing. Poor weather this week also may have been a factor in Wednesday's Airblue plane crash that killed 152 people in Islamabad.

In the Swat Valley, residents were forced to trudge through knee-deep water in some streets.

A newly constructed part of a dam in the Charsadda district collapsed, while the UN said it had reports of 5,000 homes underwater in that area.

Pakistan's poorest residents are often the ones living in flood-prone areas because they can't afford safer land.