The New York Times has claimed in a report that Bo Xilai, the Chinese politician, ran an extensive phone-tapping system that spied on high-level officials, including the president, and this contributed to his downfall.
Bo is currently under investigation for "serious discipline violations", but according to the report published on Thursday, another key reason for his downfall was his use of phone tapping in the large southwestern municipality of Chongqing which he headed until his removal in March.
Bo had been widely expected to ascend to the highest nine-man Communist Party committee that runs China, later this year, but was removed recently in a scandal that has shaken Chinese politics.
Adding to the tension, Bo's brother, Bo Xiyong, resigned as vice-chairman of China Everbright International on Thursday, in what analysts say is a signal of widening scrutiny on the family.
This comes after Gu Kailai, Bo's wife was talen into custody, and is being investigated for involvement in the alleged murder of a British businessman.
President's 'call tapped'
The ambitious Bo tapped the phones of nearly all high-ranking leaders who visited Chongqing, keen to stay apprised of what they were saying about him as he angled for the top leadership position, the New York Times said, quoting sources with party links.
On one occasion, anti-bugging devices used by central government authorities detected that a phone call to Chongqing by President Hu Jintao was being tapped, it said.
The discovery by secrecy-obsessed central government officials led to an investigation that helped bring Bo down, it said.
The scandal burst into the open in February when Bo's right-hand man, Wang Lijun, fled in fear to a US consulate in China, reportedly demanding asylum and handing over information on his former boss.
He subsequently left the consulate and has since been in Chinese custody, but the incident triggered the rapid unravelling of Bo's fortunes and those of his family.
Casualty of drama
As Chongqing's Communist Party chief, Bo launched a prominent "Red revival" that included the public mass singing of Communist revolutionary songs.
He also launched a fierce anti-crime crackdown that critics say got out of hand and led to the widespread trampling of legal rights.
Bo Xiyong's resignation made the brother the latest family casualty of the drama.
He stepped down "in order to minimise any possible adverse impact on the company of certain reports recently published by the media on his family background", according to a company notice issued on Wednesday to the Hong Kong stock exchange.
The Bo affair has proven a massive embarrassment to the Chinese government, which had been keen to project an image of unity and rectitude as it gears up for the sensitive, once-a-decade transition to a new leadership line-up later this year.