By Ben Blanchard and Benjamin Kang Lim
BEIJING (Reuters) - China's ruling Communist Party announced a corruption investigation into a one-time senior aide to former president Hu Jintao on Monday, as President Xi Jinping opens another front in his sweeping battle against deep-rooted graft.
In a terse and brief statement on its website, the party's anti-corruption watchdog said that Ling Jihua was being investigated for "suspected serious discipline violations", the usual euphemism for graft. It gave no other details.
But two sources with ties to the leadership said that Ling, who heads a party body charged with reaching out to non-Communists and holds a rank equivalent to a vice premier, may escape prosecution.
"He is under investigation, but it does not necessarily mean he will be prosecuted," one source with ties to the leadership told Reuters, speaking on condition of anonymity.
"This is Xi Jinping being fair," the source added, meaning that the president is keen to show his campaign will target anyone and that nobody is safe, no matter what their party affiliations.
Several allies of another former president, Jiang Zemin, have also been targeted, including former Chongqing party boss Bo Xilai and former domestic security chief Zhou Yongkang.
"Xi is not targeting a specific faction," said the second source. "Hu Jintao's men are also being investigated."
Ling Jihua was demoted in September 2012 after sources said his son was involved in a deadly crash involving a luxury sports car.
The car, a Ferrari according to some of the sources, crashed in Beijing in March 2012 in an embarrassment for the ruling Communist Party, which is sensitive to perceptions that children of top party officials live rich, privileged lifestyles completely out of touch with the masses, the sources said.
Ling was dropped from his post as head of the party's General Office of the Central Committee, a powerful post similar to cabinet secretary in Westminster-style governments.
He was then appointed as minister for the less influential United Front Work Department, which is in charge of co-opting non-Communists, religious groups and ethnic minorities.
As of Monday evening, Ling's picture and biography were still on the United Front's website, implying that despite the probe he still has his job.
It was not possible to reach him for comment and it is not clear if he has a lawyer.
Speculation about Ling's fate had been running high after a probe into his older brother, Ling Zhengce, was announced in June, for suspected "serious discipline and law violations".
After Ling Zhengce fell, the official Xinhua news agency noted cryptically that "having somebody in the palace won't help", in pointed reference to his family connections.
However, last week Ling Jinhua had a 4,000 character essay published in a major party journal, Qiushi, about the importance of maintaining unity for the country's ethnic minorities, in which he mentioned Xi's name at least 15 times.
China's campaign against official corruption has intensified since Xi took over as president, with several senior government figures and state company executives in detention.
Zhou's arrest was announced earlier this month and the government is also investigating Xu Caihou, the retired deputy head of the powerful Central Military Commission.
(Reporting by Kevin Yao and Ben Blanchard; Editing by Jeremy Laurence and Mike Collett-White)