China faces a serious terror threat, the foreign ministry said Monday after a fiery attack in Tiananmen Square and domestic media reports of nearly 200 "terrorist" incidents in Xinjiang last year.

A video in which a militant Islamic group called the Tiananmen attack a "jihadi operation" and predicted further violence affirmed the threat that China faces, foreign ministry spokesman Qin Gang said at a regular briefing.

The video "completely revealed this organisation's terrorist nature and made clear the truth of the incident to those who previously questioned its nature", he said.

Qin identified the organisation behind the video as the East Turkestan Islamic Movement (ETIM), which the United Nations lists as a terrorist group and which China claims has separatist aims in Xinjiang.

Beijing has pointed to violent incidents in the far-western region as evidence of rising extremism among mostly Muslim Uighurs, the area's largest ethnic group.

It has blamed several deadly attacks in Xinjiang this year, along with the Tiananmen Square incident, on "terrorists" from the region.

But analysts have questioned the strength of ETIM, while rights groups say China exaggerates the threat to justify harsh policies in Xinjiang.

Information in the region is tightly controlled and Uighurs complain of cultural and religious repression as a catalyst for clashes.

Qin's comments came as the Shanghai-based Oriental Outlook said more than 190 "terrorist" attacks were logged in Xinjiang last year, rising "by a significant margin" from 2011.

Violent assaults in the name of "jihad" have been increasing rapidly since 2009 and were the biggest threat to the region, said the magazine, which is owned by the official Xinhua news agency, citing local police authorities.

Most of the attackers were in their early 30s or younger and increasingly act in small groups or individually as "a lone wolf", it added.

The Tiananmen crash killed two tourists and injured 40 other people, with the three attackers inside the vehicle also dying after they set it ablaze.

It was not clear whether the video Qin cited, which was reported by the US-based monitoring group SITE, included an explicit claim of responsibility.