At least 66 people were killed and hundreds were injured when two passenger trains slammed into each other in eastern China early Monday.
One of the trains, a high-speed passenger carrier, jumped its tracks and slammed into another train, according to reports.
Ten cars went off the tracks and into a ditch.
The collision happened in Shandong province at 4:40 a.m. in the city of Zibo, reports the official Xinhua News Agency.
"Witnesses report a horrific scene," said CTV's Steve Chao, reporting from Beijing.
"They talk about how ambulances took three hours to get all the injured from the wreck to the hospital, and at this point officials are predicting many more people who are in serious condition in hospital, won't make it."
According to reports on Monday, 70 people were in critical condition following the crash, including four French nationals who were taken to hospital with broken bones, Xinhua reports.
There were mixed reports about the number or people hurt in the crash.
State-run television reported that 247 were injured, while Xinhua said 400 had been taken to hospital.
No foreigners were killed.
The train that jumped the tracks was on its way from Beijing to the coastal vacation city of Qingdao.
The second train, which also skipped off the rails, but remained upright, was travelling from Yantai to Xuzhou.
Terrorism was ruled out with reports stating that the accident was blamed on human error, and that two high-ranking officials from Shandong province had been fired.
In January, 18 people were killed in Shandong when another high-speed passenger train slammed into a group of workers near the city of Anqui.
Chao said the fact the officials were fired just hours after the accident suggests there were major safety deficiencies.
"This is extremely rare. Usually it takes a week and an investigation but they were fired immediately suggesting there were some longstanding problems in that province," Chao said.
He pointed out that the accident happened at a time when the trains were packed with people who were travelling home ahead of the May Day long weekend -- likely contributing to the high death toll.
There is no word on the total number of people travelling on both trains when the accident occurred.
Images published by Xinhua showed rescuers pulling passengers from an overturned train carriage, while survivors wrapped in white sheets, stood by.
One survivor told Xinhua that most passengers were on the overnight train were asleep when the crash happened.
"I suddenly felt the train, like a roller coaster, topple ... to one side and all the way to the other side. When it finally went off the tracks, many people fell on me," a passenger with the surname Zhang was quoted as saying.
Zhang, 38, said local villagers used farm tools to smash train windows to pull out trapped passengers.
"I saw a girl who was trying to help her boyfriend out of the train, but he was dead," she said.
Nine hotels and 34 rescue centres were set up to care for the survivors and their families, according to Xinhua.
Chinese President Hu Jintao and Premier Wen Jiabao were reportedly monitoring the situation.
