Beijing - Five people were killed and 38 were injured after a vehicle ploughed into crowds in Beijing's Tiananmen Square on Monday and caught fire, police said.
The blaze sent clouds of smoke billowing into the air near a giant portrait of Mao Zedong that hangs at one end of the square, the site of pro-democracy protests in 1989 which were brutally crushed by the authorities.
Witnesses and reports said the SUV vehicle drove along the pavement outside the Forbidden City, the former imperial palace, before crashing - prompting speculation the incident was intentional.
Immediately afterwards a security operation swung into force on the vast plaza, the symbolic centre of the Chinese state.
"I saw a car turn a bend and suddenly it was driving on the pavement. It happened fast but looked like it knocked people over," one eyewitness, who did not want to be named, told AFP.
"I heard an explosion and saw fire. The scene was very frightening," he added. "There were paramilitary police who told people to get back into their cars and stop taking pictures."
Images posted on Chinese social media sites showed the blazing shell of the SUV and a plume of black smoke rising near a portrait of communist China's founder that hangs on the Forbidden City's towering wall, while crowds looked on.
Several pictures posted online were deleted within minutes, streets leading to the square were blocked off and barriers were erected.
Two AFP reporters were temporarily detained close to the site and images were deleted from their digital equipment.
Tiananmen Square is generally kept under tight security, with both uniformed and plainclothes personnel deployed. Many are equipped with fire extinguishers.Social media users speculated that the car was crashed intentionally.
"Is this the 2013 Tiananmen self-immolation incident?" asked the writer of one post. "There's still a person inside the car!"
Around 120 Tibetans have set themselves alight since February 2009 in Tibet itself and adjoining regions of China, in protest against what they see as oppression by Beijing.
