Terrorist organization the East Turkistan Islamic Movement (ETIM) was behind this week's suicide attack in Beijing's Tian'anmen Square, China's top security official said.

"This violent terrorist incident in Beijing was organized and premeditated by the ETIM, which is entrenched in central and western Asian regions," said Meng Jianzhu, chief of the Commission for Political and Legal Affairs of the Communist Party of China Central Committee.

Meng was speaking to Hong Kong-based Phoenix TV.

He made the comments, without giving further details, on the sidelines of a regional security meeting of the Shanghai Cooperation Organization (SCO) in Tashkent, capital of Uzbekistan, on Thursday.

Two people were killed and another 40 injured at noon on Monday when Usmen Hasan, his mother Kuwanhan Reyim and his wife Gulkiz Gini, from the Xinjiang Uygur autonomous region drove a jeep into a crowd after crashing into a guardrail on the Jinshui Bridge, which spans the Forbidden City moat.

Two knives, an iron baton and flags related to religious extremism were found in the jeep, Xinhua News Agency reported.

Five accomplices, also from Xinjiang, were arrested. Police found knives and at least one "jihadist" flag at the temporary residence of the suspects, who admitted that they knew Usmen, and to conspiring to plan and carry out the attack.

On Friday, public security authorities released fresh details of the attack. All the eight people came from Hotan in Xinjiang. They prepared 40,000 yuan ($6,570) for the attack and collected 400 liters of gasoline from various gas stations.

They had checked the site three times before they launched the attack, according to a report by China Central Television.

The United Nations and the United States listed the ETIM — which wants independence for an "Eastern Turkistan" — as a terrorist organization in 2002. China listed it as one of the four terrorist organizations related to "Eastern Turkistan" forces in 2003.

China said the group was responsible for an attack on armed police in Kashgar on Aug 4, 2008, four days before the Beijing Olympics.

Fourteen officers were killed after being hit by a truck driven by an attacker. Earlier that year, police busted a terrorist cell run by the ETIM that had been plotting to carry out suicide attacks, poisonings and kidnappings of Olympic athletes.

Ma Pinyan, a senior anti-terrorism researcher and deputy director of the ethnic and religious study center at the Xinjiang Academy of Social Sciences in Urumqi, said, "ETIM, which is one of the main terrorist groups posing a severe threat to Xinjiang, has been the subject of crackdowns by the Chinese authorities for years.

"As a result, border areas with China in neighboring countries have become hotbeds for its activities, which are aimed at continuously providing training for people in Xinjiang and masterminding attacks."

Security in Urumqi has been stepped up since the day of the attack.

Meng briefed fellow SCO members Russia, Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan, four of which share a border with Xinjiang, about the attack.

He said many countries, including China, are under threat amid increasing global terrorist activities and China is more determined to fight against violence and terrorist crimes.

Zhang Xinfeng, director of the executive committee of the SCO's Regional Anti-Terrorism Agency, said it will help China "get to the bottom of the case" by cooperating with the investigation, Xinhua reported.

Yang Yujun, a Defense Ministry spokesman, said on Thursday the Chinese army will combat various terrorist activities when necessary according to government instructions under the National Defense Law and the Emergency Response Law of China.

He said terrorism is an international enemy that many countries' armies have been ordered to combat.

Pierre Picquart, a China observer and professor of geopolitics at the University of Paris-VIII, said China is no exception to terrorism, as it is becoming more open.

"French President Francois Hollande has expressed his willingness to have more political exchanges with China, which should also include cooperation on fighting against global terrorism," he said.

"This type of terrorist attack can happen anywhere, in any city, in any country. Therefore, we have to take effective and important action and cooperate to fight all types of terrorism."

Li Xiang in Paris contributed to this story.