China's top security official blamed a little-known militant group for this week's suicide car crash that killed five people in the heart of the capital, renewing Beijing's disputed claim that the country faces a significant, organized terrorist threat.

Meng Jianzhu offered no details of the allegations against the East Turkestan Islamic Movement, and it isn't clear whether the group has the ability to orchestrate terror strikes. Beijing says the movement is dedicated to the violent overthrow of Chinese rule in the northwestern region of Xinjiang that is home to the country's Turkic Muslim Uighur minority.

Police said they found flags imprinted with religious slogans among items in the SUV used in the attack and at the temporary lodgings of five arrested suspects.

China's government has said previous attacks in Xinjiang were inspired by jihadi propaganda and has linked several of them directly to the ETIM.

Meng named the group in an interview with Hong Kong-based Phoenix Television during a visit to the capital of Uzbekistan to attend a regional security summit.

"Behind the instigation is the terrorist group East Turkestan Islamic Movement entrenched in central and west Asian regions," Meng, chief of the Commission for Political and Legal Affairs of the ruling Communist Party, said in the interview.

No one has claimed responsibility for Monday's attack.

On Friday, additional vehicle barriers were in place along the route the SUV took as it plowed through crowds toward Tiananmen Gate, killing three in the car and two tourists, including a Filipino woman, and injuring dozens. Extra police conducted random bag and ID checks among the tourists circulating beneath the huge portrait of Mao Zedong hanging from the gate where the vehicle burst into flames after crashing.

Security has been strengthened in Xinjiang, and Uighurs in Beijing have been subjected to increased police checks.

Beijing police said the perpetrators were a man with a Uighur (pronounced WEE-gur) name, his wife and his mother. Police have arrested five people — identified with typically Uighur names — on suspicion of conspiring in the strike — the city's first in recent history.

The 9 million-strong Uighurs have close cultural and linguistic ties to Turkic peoples of Central Asia and traditionally follow a moderate version of Sunni Islam. Many complain of Chinese cultural and religious restrictions and discrimination by the country's ethnic Han majority.

The United States placed the ETIM on a terrorist watch list following the Sept. 11 attacks, but quietly removed it amid doubts that it existed in any organized manner. It is still listed as a terrorist group by the United Nations and a handful of other Asian nations, as well as China.

Uighur activists say Beijing places the blame on alleged terrorists in order to ignore very real discontent over economic and political discrimination among Uighurs. The most prominent exiled Uighur leader, Rebiya Kadeer, whom Beijing blamed for orchestrating deadly 2009 rioting in Xinjiang, disavows violence and says Beijing is seeking to blunt overseas criticism of its policies by linking itself to the global anti-terrorist struggle.

Information about the group's organization and capabilities is difficult to come by, particularly its ability to launch attacks outside of Xinjiang, although University of Michigan Xinjiang expert Phillip Potter says the Pakistan-based ETIM leadership has close ties with the Taliban and could be gaining in sophistication.

"The result is cross-fertilization between previously isolated movements, leading to the diffusion of tactics and capabilities that have the potential to increase the sophistication and lethality of terrorism in China," Potter wrote in a forthcoming article for the publication Strategic Studies Quarterly.

In Washington, State Department spokeswoman Jen Psaki said America supported China's investigation into the matter, but declined to call it a terrorist attack and reiterated U.S. support for Uighur human rights.