SHANGHAI (AP) -- The driver of a minivan hauling gas canisters set fire to his vehicle while smoking a cigarette Friday, plowing into pedestrians and bursting into flames, leaving 18 people injured in the heart of the Chinese financial hub of Shanghai.
Police ruled out the possibility of a deliberate attack and described the crash as an accident. The 40-year-old minivan driver, whom police identified only by his surname Chen, lost control after a fire erupted in his van, which held several plastic bottles of gasoline as well as six canisters of liquid gas.
A cigarette butt found by investigators in the van likely started the fire, Shanghai police said in a statement Friday evening. They said Chen had been alone in the vehicle.
Chen was being treated for severe smoke inhalation and was in a coma, and nine other people were still hospitalized, police said. Chen works for a Shanghai metals company and had no criminal record but is now under suspicion for transporting dangerous materials.
The incident, which took place during a morning commute period near Shanghai's People's Park and a vast plaza that is also home to the headquarters of the municipal government, provided a brief scare for a city that was hosting British Prime Minister Theresa May. Vehicle attacks by extremists have killed scores globally in recent years, including some in Chinese cities.
The minivan veered onto a sidewalk and burst into flames around 9 a.m. on busy Nanjing West Road in the heart of Shanghai, a metropolis of almost 25 million people that is widely regarded as China's most cosmopolitan city.
"It couldn't stop, crashed into the corner and caught fire," said a cleaner who works in a building across the street from the crash site. Like many Chinese, she asked only to be identified by her surname, Xu.
She told The Associated Press she saw smoke coming out of the van as it drove down the street before careening out of control.
The website of the local Xinmin Wanbao newspaper and other local news media said the van struck five to six people waiting for a light change at a busy pedestrian crossing.
Videos on social media showed injured people lying on the pavement next to a Starbucks cafe and others pinned under the tires of the van. Firefighters were seen trying to put out a blaze inside the vehicle.
Xu, the cleaner, said she saw two men struggling to pull a person out of the van. "Other people told them to stop. Then the police and ambulance arrived," she said.
A man who witnessed the crash on his way to People's Park said in a video interview carried by Chinese media that the minivan seemed to be moving fast as it veered across the road.
"The minivan did not slow down. The driver must have been in a panic at the time. He didn't slow down and just directly crashed," said the witness, who wasn't identified. "It was on the other side of the road and made a turn over to this side. People saw it and quickly tried to get away but a lot of people were still hit."
The man said firefighters removed liquefied gas canisters from the vehicle.
At the nearby Changzheng Hospital, Shanghai resident Liu Axing told AP that his daughter, Liu Jianying, was crossing the street on her way to work when she was struck by the van.
She was undergoing surgery for a broken shoulder and pelvis, Liu said as he pulled up a picture on his phone of his daughter pinned under the vehicle's front wheel, seemingly unconscious.
Three people were more seriously injured than her, Liu added.
A relative of one patient in the emergency room, who declined to be identified, said at least five or six crash patients were being treated there.
Before police declared the crash an accident, there were fears of a repeat of 2013, when five people, including three attackers, were killed when a four-wheel drive vehicle plowed into a crowd in front of Tiananmen Gate in the center of Beijing. The attack was blamed on separatist extremists from the Turkic Muslim Uighur ethnic group native to northwestern China.
Vehicle attacks have also taken place in Europe and the United States, most recently in October, when eight people in New York City were killed by an attacker claiming allegiance to the Islamic State group.
Friday's crash occurred just as the British prime minister was speaking at a business event in Shanghai. May's speech was at a forum in the Lujiazui district on the opposite side of the Huangpu River from People's Park.
Other speakers at the event included Li Shufu, the chairman of Chinese carmaker Geely, and Nobel Prize-winning physicist Kostya Novoselov. May on Thursday met with Chinese President Xi Jinping in Beijing as part of her three-day visit aimed at establishing a new trading relationship after Britain leaves the European Union.
The crash came at the start of the Lunar New Year travel period, when hundreds of millions of people return to their hometowns for the most important family holiday of the year. During the weeks-long travel period, authorities emphasize safety on the road and aboard planes, trains and ferries.
Li Jing, a professor of disaster management at Beijing Normal University's School of Social Development and Public Policy, said the incident also points to the need for increased safety awareness in China, where gas canisters and other highly dangerous objects are sometimes transported on flatbed tricycles even in major cities such as Beijing.
"Because of his complete ignorance of safety rules, his action has amplified harm and risk to the public resulting in such casualties," Li said of the driver. "It indicates how urgent it is for the government to step up promotion of public safety knowledge and awareness."
Hours after the crash, Shanghai police posted a social media message warning drivers to "never, ever smoke" — or toss cigarette butts in proximity of flammable objects.