China is facing "unprecedented national security risks", the ruling Communist Party's top leaders said Friday after a monthly meeting led by General Secretary Xi Jinping.

The elite 25-member Politburo said in a statement that "some of the security challenges and risks are unpredictable so the country must always be mindful of potential dangers", according to the official Xinhua news agency.

Beijing will protect its national security in "a pattern with Chinese characteristics," it added, without elaborating.

China's relations with its Asian neighbours -- particularly Japan -- have been strained in recent years by a series of territorial rows in the East and South China Seas.

It also sees the US foreign policy "pivot" to the Asia-Pacific region as an attempt to contain it, a claim Washington denies.

Beijing maintains that its actions are solely in defence of its own sovereign territory.

At the same time, China has cited cybersecurity as a growing concern, with Beijing frequently describing itself as a victim of hacking -- while last May Washington charged five members of a shadowy Chinese military unit with hacking US companies to winkle out their trade secrets.

Violence within China's borders has also intensified over the past year, with at least 200 people killed in a series of clashes and increasingly sophisticated attacks in the restive Xinjiang region and beyond it.

The state-run China Daily newspaper reported Friday that prosecutors in the far-western region -- home to the mostly-Muslim Uighur minority -- had approved the arrest of 27,164 criminal suspects in 2014, up more than 95 percent on the previous year.

Beijing, which blames Xinjiang-related violence on "religious extremists," "separatists" and "terrorists," has responded by launching a severe crackdown in recent months, with around 50 executions and death sentences publicly announced since June.

The ruling party has also warned that terrorists from outside of the country's borders -- including an organisation it calls the East Turkestan Islamic Movement (ETIM) -- are seeking to enter and launch attacks.

But Beijing has produced little evidence linking the attacks to organised extremist groups, and some analysts doubt that ETIM exists as a significant force in the region.