Workers stand before a police barrier outside Tiananmen rostrum in Beijing on Monday after a jeep crashed into the crowd in Tiananmen Square and burst into flames, killing five and injuring 38, police said. Photo: AFP

China's top security official said that the recent deadly car attack in Tiananmen Square was planned by the East Turkistan Islamic Movement (ETIM), a separatist group, designated as a terrorist organization by the US and UN, Hong Kong-based Phoenix Television reported late Thursday. 

Meng Jianzhu, chief of the Commission for Political and Legal Affairs of the Communist Party of China Central Committee, made the comments at a meeting of the Executive Committee of the Shanghai Cooperation Organization (SCO) Regional Anti-Terrorism Agency, during his visit to Uzbekistan.

An SUV ploughed through bystanders in Tiananmen Square on Monday and burst into flames, killing the three people in the car and two bystanders and injuring 40 others. Beijing police arrested five people from Xinjiang who had knives and a jihadist flag.

Public security authorities revealed that eight people had driven from Hotan in Xinjiang to Beijing and surveyed the site three times before the attack, CCTV News wrote on its Sina Weibo account late Friday.

Seven of them are from three families and hid in Beijing's Xicheng district, and also raised 40,000 yuan ($6,572) to carry out the attack.

Meng called for deeper anti-terrorism cooperation among SCO members on Friday, according to the Xinhua News Agency.

"We believe many countries, including China, are currently under threat amid rising global terrorist activities and China is more determined to fight against violence and terrorist crimes," Meng said.

"Countering such terrorist activities requires deeper cooperation among SCO members and improving its anti-terrorism mechanism as well as mutual understanding and trust," Li Wei, director of the anti-terrorism study center at the China Institutes of Contemporary International Relations, told the Global Times on Friday.

Meanwhile, Chinese foreign ministry spokeswoman Hua Chunying said on Friday that the case is still under investigation.

Hua noted at a regular news conference that ETIM has been the most direct and real threat to the country's security and China will continue to work with other members of the SCO to fight against terrorist activities and ensure the stability and safety of the region.