BEIJING - Nine suspects have been detained over alleged syringe attacks in three new places in China's Xinjiang region, after hundreds were stabbed in the flashpoint city of Urumqi, an official said Friday.

Six were held this week in Hotan, two in Altay and one in Kashgar, an official in the press department of the Xinjiang regional government told AFP, refusing to give his name.

The state-run China Daily reported that while several syringe attacks had been reported in each city, more than half of them had not been confirmed or turned out to be "false alarms".

Authorities in Urumqi, the Xinjiang regional capital, have detained a total of 45 people on suspicion of carrying out needle attacks since mid-August in the city, the scene of deadly ethnic unrest in July that left nearly 200 dead.

Of the more than 500 stabbings confirmed by police, 171 victims have shown "obvious" signs of an attack, the China Daily said. Officials have said they have so far seen no evidence that the syringes contained dangerous substances.

The attacks sparked mass protests earlier this month in Urumqi, with demonstrators demanding that the government do more to ensure public safety. Five people were killed, according to officials.

The head of the Urumqi branch of the Communist Party and Xinjiang's top police official were both sacked in the wake of the needle attacks and subsequent protests.

The syringe stabbings have caused ethnic tensions to spike once again in the city, where unrest erupted in July pitting minority Uighurs against members of China's dominant Han ethnic group.

Most of the 197 people killed in the violence were Han Chinese.

One official with the Xinjiang public security department, Du Xintao, has dubbed the needle stabbings "terror attacks". Han residents of the city have said Uighurs were to blame.

The mainly Muslim Uighurs have long chafed at what many say has been decades of Chinese oppression and unwanted immigration of millions of ethnic Han.