The first accident occurred at around 2:18 a.m. in northwest China's Shaanxi Province, when a fully-loaded double-decker sleeper rammed into a methanol-loaded tanker, triggering a fire that instantly engulfed both vehicles and leaving 36 people aboard the bus dead, including the bus driver.

Only three people escaped from the bus and two of them suffered serious burning injuries. The two drivers of the tanker, who were not hurt in the collision, were taken into police custody.

In another accident, a van carrying 12 people crashed into a heavy-duty truck Sunday afternoon on an expressway in southwest China's Sichuan Province, leaving 10 people on the van dead at the scene and another two badly injured.

The two injured were sent to a nearby hospital and one died at 3:30 p.m.after rescue efforts failed.

The truck was at roadside for tire repair when the van rear-ended with it, according to local work safety authorities.

In Shaanxi's accident, the 39-seat bus was full at the time of the crash, which occurred about 200 meters from Ansai service station on the Baotou-Maoming expressway linking northern China's Inner Mongolia Autonomous Region and Guangdong Province in the south.

The bus, which was heading from Inner Mongolia's capital Hohhot to Shaanxi's capital city of Xi'an rear-ended the tanker, which just returned to the expressway after an early morning rest stop in the station close to Yan'an City in Shaanxi.

A staff member of a nearby gas station said he heard the sound of the crashing, which seemed not loud. "It sounded like tire bursting," said the man, who did not give his name.

After a short while, fire broke out at the scene. He and his colleagues rushed to the scene with extinguishers, hoping to put out the blaze.

"The fire was so big that our efforts were only proved in vain," he said.

Fire brigade in Ansai County received alarm call at about 2:40 a.m. and three fire engines and 10 fire fighters were immediately dispatched to the scene, said Wei Chaoyang, director of the fire brigade.

"After arriving at the scene, we found that the fire was very big and the methanol that leaked from the tanker was keeping running to the bus and nearby drainage, forming a 'running fire' that hampered our rescue," Wei said.

The fire was finally put out at about 3:42 a.m., according to Wei.

Both witnesses at the scene and fire fighters believed that leaked methanol from the tanker ran to the bus and caught fire, trapping the passengers who were not able to escape within a short time.

Meanwhile, it was in the wee hours of the morning when the accident happened and most passengers were in deep sleep, leaving them little chance of survival from the inferno, they said.

The front end of the bus had been seriously deformed in the accident and the whole body of the bus was only left with a charred skeleton frame, according to the Xinhua reporters at the scene.

Two of the three survivors suffered serious burnings and inhalation injuries, while another survivor, Wang Xianze, was only slightly injured.

Wang, from Yunyang County in southwest China's Chongqing Municipality, recalled that when the accident happened, he was sleeping on his upper berth, which was at the last row on the left side.

"It was like an explosion, and I was hardly able to breathe due to the shocking wave and not aware what had happened," Wang said.

"After regaining my consciousness, I fumbled about with my body and head and found I was not injured. So I opened the window by my side and jumped out," he said.

Wang's leg was scratched while he was jumping out, and he was taken to hospital by a passer-by.

He said it was within only about two minutes that he escaped, while many others inside even had no time to take actions before they were engulfed by the fire.

The tanker, owned by Mengzhou No. 1 Transport Co., Ltd. in central Henan Province, was transporting methanol from Shaanxi-based Yulin Energy and Chemical Co., Ltd to the eastern province Shandong. The bus belongs to Hohhot Municipal Transport Group.

The State Council has sent an investigation team to Yan'an to look into the accident and oversee the rescue efforts, according to the State Administration of Work Safety (SAWS).

The team, headed by SAWS deputy director Sun Huashan and Vice Minister of Public Security Huang Ming, called an on-site meeting in the afternoon, vowing to investigate and affix the responsibility for the accident.

In the meantime, lessons must be drawn from the accident so that such tragedies will not reoccur, said an official with the investigation team.

Local governments both at provincial and municipal levels will ascertain the identities of the deceased as soon as possible, an official with the Shaanxi provincial government said.

Further investigations into the two accidents are under way.

Traffic accidents on China's roads result in about 70,000 deaths and 300,000 injuries each year, according to the Ministry of Public Security. Speeding, fatigue, drunk-driving and poor road conditions are usually blamed.

Sunday's road accident in Shaanxi is the worst in China since July last year when a fire on an overloaded sleeper bus killed 41 passengers and injured six others on an expressway in central China's Henan Province.