Chinese officials on Tuesday vowed severe punishment for the mob in the deadliest riot since New China was founded in 1949, while international organizations urged restraint in China.

United Nations (UN) Secretary General Ban Ki-moon on Monday led international calls for restraint in China after Sunday's riot in Urumqi which killed 156 people and injured 1080, the largest number of casualties in any single incident of its kind in six decades.

Wherever it is happening or has happened the position of the United Nations and the secretary general has been consistent and clear: that all the differences of opinion, whether domestic or international, must be resolved peacefully through dialogue, the UN chief told a press conference when asked about events in Xinjiang.

Governments concerned must also exercise extreme care and take necessary measures to protect the life and safety of the civilian population and their citizens and their properties, and protect freedom of speech, freedom of assembly and freedom of information, he added.

Britain echoed the call from UN for restraint.

Prime Minister Gordon Brown's spokesman said the British government was concerned about the reports of violence and called for problems in Xinjiang, home to ethnic Muslim Uighurs, to be resolved through dialogue.

Of course we are concerned about the reports of violence and the scale of the loss of life and I think we would urge restraint on all sides and, where possible, for problems to be resolved through dialogue, the spokesman said.

Police in Xinjiang have arrested 1,434 suspects over Sunday's deadly riot, including 1,379 men and 55 women. They are said to have conducted violent acts of killing, beating, smashing, looting and burning.

The Sunday violence in Urumqi was an evil killing, fire setting and looting, said Foreign Ministry spokesman Qin Gang on Tuesday.

The rioters violated laws and harmed the fundamental interests of all Chinese ethnic groups, said Li Zhi, Communist Party of China (CPC) chief of Urumqi.

The violence is a preempted, organized violent crime. It is instigated and directed from abroad, and carried out by outlaws in the country, Qin said, noting that the evidence was irrefutable and conclusive.

Xinjiang police said Monday they had evidence that separatist World Uyghur Congress leader Rebiya Kadeer masterminded the riot.

According to a local official, the Chinese authorities had evidence that Rebiya Kadeer used the Internet and other means of communication to mastermind the riot in Xinjiang.

Internet was cut in parts of Urumqi following the deadly riot to prevent violence from spreading. Qin said this measure was taken in order to deal with the incident and safeguard local stability. was blocked in the mainland on Monday, while, Twitter's Chinese equivalent, remained in operation. However, searches for Xinjiang, Urumqi Uighur or Riot produced no results.

Independent information about the riot, including photos, poured into online forums and blogs. But such Web pages were soon deleted, while mobilephone services were briefly unconnected in the afternoon.

Foreign journalists, about 60 in number, were in Xinjiang on a reporting trip arranged by the Information Office of the State Council, the Chinese Cabinet. A media center had been set up in Hoi Tak Hotel for reporters and internet was provided for them exceptionally.

The riot has destroyed the spiritual support with which the terrorist, separatist and extremist forces cheated the people to participate in the so-called Jihad, Lequan Wang, chief of the Xinjiang Communist Party of China (CPC), said in an interview with Xinjiang TV on Monday.

Those rioters are not representatives of the Uygur people, said Abudurekefu Akhond, member of the standing committee of the China Islamic Association. The Islam creed advocates peace and harmony. Different ethnic groups should show respect to and learn from each other with mutual understanding. he added.

Though Han Chinese wreaked revenge on Uighurs on Tuesday, they were stopped by the riot police. Crowds vented their anger by throwing rocks at a mosque and smashing restaurants and shops owned by Uighurs.

I don't think violence is a good way for solutions, said Aniwar Maimaiti, a Uygur from Aksu in southern Xinjiang. A better way is to increase communications. The 33-year-old salesman added.

Riot police armed with tear-gas bombs, rifles, batons and shields could be found patrolling on the street near the hotel, with armored vehicles rolling by.

While those under arrest might be released if no serious criminal records were found, authorities would not let pass those who were still at large.

China, by rule of law, would not wrong one innocent person, nor setting free any evil one, said Foreign Ministry spokesman Qin.