Runaway train cars carrying a lethal mix of fuel and chemicals derailed, caught fire and then exploded hours later Wednesday in northeast Iran, killing more than 200 people, injuring at least 400 and leaving dozens trapped beneath crumbled mud homes.
Many of those reported dead were firefighters and rescue workers who had extinguished most of the blaze outside Neyshabur (search), an ancient city of 170,000 people in a farming region 400 miles east of the capital, Tehran (search).
The dead also included top city officials -- including Neyshabur's governor, mayor and fire chief as well as the head of the energy department and the director-general of the provincial railways -- who had all gone to the site of the derailment, the official Islamic Republic News Agency reported.
The explosion devastated five villages, where authorities rushed in blood supplies and appealed through loudspeakers for donors. Hardest hit was Hashemabad, where 41-year-old Zahra Rezaie, whose mud home was near the tracks, was cooking lunch for her family when she heard the explosion and felt the ground shake. Then the ceiling collapsed.
"It knocked down and broke some dishes. I was sure it was an earthquake, and my first thought was to rush to the school and save my children," Rezaie told The Associated Press. Her children were safe.
An AP photographer who arrived in Dehnow, one of the severely damaged villages close to the train tracks some 500 yards from the blast, said the village's homes were flattened.
"The houses are all built of clay, and nearly every one has been destroyed, like they had collapsed in an earthquake," Hassan Sarbakhshian said. "Everyone appears to have been evacuated," he said, adding he could see thick, black smoke billowing about 500 yards ahead.
Rescue workers, aided by cranes and giant floodlights, worked into the night shrouded in toxic fumes, as they searched for dozens of people thought to be trapped in their clay homes devastated by the blast.
The blast was so powerful that windows were shattered as far as six miles away. In an apparent indication of the explosion's force, Iranian seismologists recorded a 3.6-magnitude tremor in the area, IRNA reported.
Many of the buildings that collapsed in a Dec. 26 earthquake in Bam, in southeast Iran, also were mud-brick structures. That tragedy killed more than 41,000 people.
Authorities were investigating what caused the 51 cars to roll out of the Abu Muslim train station, outside Neyshabur, at 4 a.m. Forty-eight of the cars derailed on reaching the next stop at Khayyam, about 12 miles away, and caught fire.
Iranian TV showed footage of black plumes of smoke and orange flames billowing into the sky from the cars, 17 of which were loaded with sulfur, six with gasoline, seven with fertilizer and 10 with cotton. Dozens of people, some wearing face masks to protect themselves from the smoke, were seen walking around or putting out flames on the scene.
Firefighters -- apparently with little experience in handing industrial chemicals -- had extinguished 90 percent of the fire when the cars exploded at 9:37 a.m., Mohammad Maqdouri, head of the local emergency operations headquarters, told Tehran television.
More than 400 people were injured, said Vahid Bakechi, a senior official in Khorasan Province's (search) Emergency Headquarters.
Eighty percent of them were injured when their homes collapsed, and the rest were either burned or hurt from the force of the explosion, said Syed Majid Taqizadeh, head of the 22 Bahman hospital. The hospital is named after the date in the Iranian calendar that coincides with Iran's 1979 Islamic Revolution.
The bulk of the injured were from the village of Hashemabad, Taqizadeh said. Other victims were found in surrounding villages, particularly Dehnow and Abdolabad.
Dozens of people remained buried under the rubble of their homes, said Saeed Kaviani, editor of the Sobh-e-Neyshabur newspaper. Iranian paramilitary Revolutionary Guards closed the immediate area, fearing more explosions.
IRNA quoted Mehran Vakili, Neyshabur's medical examiner, as saying that by Wednesday evening 180 bodies had been recovered. The dead included 182 fire and rescue workers.
"The scale of the devastation is very great, and the damage appears more than initially thought," said Vahid Bakechi, of the Khorasan Province's Emergency Headquarters.
In New York, U.N. Secretary-General Kofi Annan conveyed his condolences to the Iranian government and the victims of the disaster, U.N. spokesman Fred Eckhard said. He added that the world body was ready to assist those affected by the tragedy.
After finding her children safe at the Hashemabad school, which was unscathed by the explosion, Rezaie went to a hospital.
"That's when I saw them bringing in many injured people ... wearing uniforms that firefighters or rescue workers wear," she said. "They told me there had been an explosion," she said.
Neyshabur is at the center of a farming region for cotton, fruit and grain. Other industries include carpets, pottery, leather goods and turquoise.
It became one of Persia's foremost cities in A.D. 400, a center of culture with several important colleges. Omar Khayyam, the 11th century Persian poet, was born in Neyshabur, and is buried there.