Beijing suspects two people from China's restive Xinjiang province are linked to the Tiananmen Square car crash that killed five people and injured 38, state media said on Tuesday.
A notice issued by the Chinese capital's police "said that a 'major case had taken place on Monday' and named two residents of Pishan county and Shanshan county of Xinjiang Uyghur Autonomous Region as likely suspects," China's state-controlled Global Times reported.
The news comes as at least one news report, citing identified sources claiming direct knowledge of the incident, said the car crash may have been a suicide attack.
"It looks like a premeditated suicide attack," a source told Reuters on condition of anonymity. The identities of the driver and two passengers inside the vehicle, all of whom died, are still unknown.
At about 12:05 p.m. on Monday, a vehicle ploughed through pedestrians in Tiananmen Square and crashed into the Jinshui Bridge outside the southern gate of the Forbidden City, where the portrait of former Communist leader Mao Zedong overlooks the square.
"We thought the jeep was heading for us, and my mother and I had no way to run from it. So we didn't move," eyewitness Wang Dake, who went to a nearby hospital with minor injuries, told the BBC.
"I thought that if the car was going to hit us, then we would die right there. But it hit the marble railing and didn't hit us," he added.
The location of the incident is a highly state-controlled area. Key political institutions surround Tiananmen Square, and, of course, the site is closely associated with China's failed 1989 democracy movement, which ended with a violent military crackdown.
After the crash a BBC news crew that had tried to take footage of the incident was detained for a short time, according to the UK news outlet, which also reported pictures of the incident posted on Chinese social media websites had been swiftly deleted.
Members of the Uyghur minority, historically the native population of Xinjiang but increasingly outnumbered by Han Chinese migrants, have been accused of terrorism in the province before. Some complain that they are victims of persecution by Beijing.