Government of Pakistan Friday kicked off an emergency rescue and relief operation after declaring emergency in the flood-hit northwestern province of Khyber Pakhtunkhwa (KP) as more than 400 have died and thousands are missing.

Pakistan also asked international community to help it fight the floods which have hit across the country, making more than one million people homeless.

Pakistan's National Disaster Management Authority (NDMA) has requested United Nations and international community for the urgent help in the country's worst flood for last 81 years which is now heading towards Southern and Western part of the country, local Television Samma reported.

According to rescue teams, hundreds of villages, bridges, roads, railway tracks, houses and billions of dollars worth properties have also been smashed in the rains and high current floods.

Pakistan Navy, Air force, Pakistan Army and dozens of other civil and government rescue teams are busy in the affected areas but those seem insufficient.

The KP government has released about 1.16 million U.S. dollars to cope with the situation in the province but the experts said the amount is too little.

More than one million people have been stranded due to floods in various parts of the country and mostly have resorted to take shelter on rooftops, trees and electricity pools.

According to the meteorological department, current recorded rains have broken the 34-year old record of torrential rains in the different parts of the country.

The rains flooded almost all the main bazaars, roads and residential areas of the provincial capital Peshawar and compelled the residents to leave their homes.

Water management authorities on Thursday night ordered to open the spill ways of the dams after water level reached at dangerous level. The country which was facing severe water shortage just a week back, but now has so much extra uncontrollable water.

The Silk Route, a business road linking Pakistan and China, has been damaged at seven different points due to rain resulted land sliding. Another road in the NW Pakistan leading to Afghanistan has been closed at Jamrud city due to floods.

The affected people are facing severe shortage of food, water and medicine. Especially many people have been reportedly bit by the snakes.

District Charsadda, a city in the NW Pakistan, has got more than 100,000 people reportedly stranded by floodwater and the city has been cut off from the other part of the area.

Three Chinese engineers along with Frontier Corps personnel are reportedly went missing in Kohistan after the flood hit the area. But 52 other Chinese engineers and their Pakistani co-workers working on a hydroelectric project in the area were rescued and lifted to the safe place through helicopters.

Provincial Information Minister Mian Iftikhar asked the people of the affected areas to shift to safer places without any further delay.

He also appealed to the Federal and other provincial governments of the country as well as to the organizations engaged in relief activities to help extend aid to calamity-hit province.

The floodwater has also entered into the residential area of the garrison city of Rawalpindi adjacent to the capital Islamabad. More than three persons were died when a two story building smashed down.

American Embassy has provided seven helicopters to the government of Pakistan which would assist in the rescue operation in the flooded areas, a spokesman of the U.S. Embassy said on Friday.

"The heavy monsoon rains have caused much suffering," said NW Patterson, U.S. Ambassador in Islamabad.

"We are working with Pakistan's government to review urgent humanitarian needs and hope to announce additional assistance very soon," U.S. Embassy quoted the envoy in its press release.