ZARAND, Iran - Tired and cold survivors of a powerful earthquake in southeastern Iran begged authorities for food and shelter on Wednesday, complaining aid was slow to reach the worst-hit mountain villages.

Iran has so far declined offers of foreign assistance to deal with the aftermath of Tuesday's tremor which had a magnitude of 6.4 and killed at least 420 people.

Hardest hit were about a dozen villages to the north of the town of Zarand, where fragile one-storey homes collapsed into piles of mud and broken tiles.

The tremor came just 14 months after a devastating quake hit the desert citadel city of Bam, in the same province, killing 31,000 people.

Some 900 were injured in Tuesday's quake, about 440 miles southeast of Tehran, and the death toll was expected to rise.

Reuters journalists witnessed a few dozen angry villagers on a high mountain road, some brandishing sticks and stones, besiege a convoy of vehicles, one of which carried Interior Minister Abdolvahed Mousavi-Lari as he toured the affected area.

"We spent the night in the cold. Where is the aid you're talking about on television?" shouted one middle-aged man as the villagers banged on the windows and roofs of the vehicles.

"My children are freezing to death. You want to kill the survivors of the earthquake," a woman shouted hysterically, clutching a rock.

Police dispersed the crowd, some of whom had tried to block the convoy's passage by lying in front of the vehicles.

But aid workers acknowledged the relief effort was still slow and patchy.

Rain and Fog

"The aid which has been distributed is tents. We're trying to establish some camps here. We haven't distributed food or blankets yet," said Red Crescent medic Farhad Fathizadeh.

"We're sorry we haven't been able to help people much but we're trying to prepare ourselves for tonight," he said.

In the village of Houdkan, shrouded in fog about 30 km (20 miles) from Zarand, dozens of green and white tents dotted the hillside, many containing two or three families.

Groups clustered around bonfires trying to warm themselves under an intermittent drizzle.

Virtually no building was left standing and those that were had been deserted for fear they could come crashing down at any moment. Black banners draped on the remaining walls announced the names of the dead.

Some 20 aftershocks, with a magnitude of up to 4.6, shook the area on Tuesday, the ISNA students news agency said.

Locals said many of those killed in Houdkan, one of the two most badly damaged villages in the region, had died while at early morning prayers in the mosque.

Kerman province Governor Mohammad Ali Karimi told local radio almost all the affected villages had received tents, blankets and food. He said search and rescue operations, hampered by poor weather and difficult terrain on Tuesday, would be wound up by noon on Wednesday.

Iran's relief efforts were broadly praised on Tuesday by various U.N. agencies who said local authorities, backed by the Red Crescent, had responded quickly and effectively, employing the lessons learned from the Bam quake.