THE death toll from the magnitude 7.3 earthquake that struck Iran's western province of Kermansh on Monday has passed 450.
It killed at least seven people and injured 535 others in Iraq.
As thousands of homeless Iranians huddled against the cold as day turned to night, rescue teams sought desperately for signs of life amid the rubble of buildings in towns and villages close to the border with Iraq.
Iran's Press TV said at least 450 people were killed and 7000 injured.
About 70,000 people were in need of emergency shelter across 14 affected provinces around the country, the Iranian Red Crescent warned.
Electricity has been cut off in many cities in both countries and fear of aftershocks has driven many people outside despite the cold.- INM
Rescue workers continued despite the difficulties posed by landslides and the health ministry put out a call for emergency blood donations.
Dozens of buildings and the only hospital in one town of 30,000 people was also badly damaged by the tremors.
At least 14 provinces in Iran had been affected, Iranian media reported.
They said a woman and her baby were pulled out alive from the rubble in Sarpol-e Zahab, which has a population of 85,000.
"We need a shelter,” a middle-aged man in Sarpol-e Zahab told state TV. "Where is the aid? Where is the help?” His family could not spend another night outside in cold weather, he said.
Relief workers said while much aid had been pledged, there was an immediate need for blankets, children's clothes, medicine and large cans to store drinking water. TV aired footage of some people weeping next to corpses shrouded in blankets.
Iran's Supreme Leader Ayatollah Ali Khamenei has offered his condolences and three days of mourning have been announced in Kermanshah. A national day of mourning was announced for Tuesday.
In Iraq, the earthquake killed at least seven people and injured 535 others, all in the country's northern, semi-autonomous Kurdish region, according to the Interior Ministry.
Many of the heavily damaged complexes in Sarpol-e-Zahab were part of construction projects under former hardline President Mahmoud Ahmadinejad. The disparity in the fatality figures between the two countries immediately drew questions from Iranians, especially because so much of the town was new.
Kokab Fard, a 49-year-old housewife in the town said that she could only flee empty-handed when her apartment complex collapsed. "Immediately after I managed to get out, the building collapsed ... I have no access to my belongings,” she said.
Reza Mohammadi, 51, said he and his family ran into the alley following the first shock.
"I tried to get back to pick some stuff, but it totally collapsed in the second wave,” Mr Mohammadi said.
Turkey, despite recent tensions over the Iraqi Kurdish Regional Government's controversial independence referendum, said on Monday it would send aid including tents, beds, heaters and food to help alleviate the situation, expressing "deep sadness” at the loss of life.
- Bethan McKernan, The Independent