Authorities in Urumqi City have banned unlicensed marches, demonstrations and mass protests, a municipal government spokesman confirmed Friday.

The announcement was publicized by the city government Thursday night, shortly after tens of thousands of people took to streets during the daytime to protest against syringe attacks in the city, said the spokesman.

"The leaflet is meant to safeguard public order, and protect the lives of the public and guarantee property safety," said the spokesman.

The five-article announcement bans all gatherings, marches or protests on roads or other public venues in the open-air without having first obtained permits from the public security department.

Also banned are weapons, knives with restricted uses, and explosives, or use of violence, and disturbances at such events, said the spokesman.

In case of violations, the public security department will disperse those gathered, and detain those who disobey the order.

Acts violating the administration of public security will be penalized, while criminal responsibility will be pursued for those suspected of having committed crimes in those gatherings, according to the announcement.

Police said that attacks with syringes against innocent people have been carried out in Urumqi since August 17. The regional health department said 476 people have sought treatment for stabbing as of midday Wednesday, of whom 89 were showing obvious signs of needle injuries.

As of Wednesday, there had been no deaths reported and no symptoms have been found of infectious disease viruses or toxic chemicals.

Police had seized 21 suspects, of whom six are in custody and four have been arrested for criminal prosecution, said the regional information office in a mobile phone text message to the public Thursday.

It also said that the court would hand down severe punishments to those found guilty.

The attacks came less than two months after the July 5 Urumqi riot when 197 people, mostly from the Han ethnic group, were killed, and 1,600 others injured.

(Xinhua News Agency September 5, 2009)