By Alistair MacDonald And David George-Cosh
In January, John Jia traveled from Canada to Shanghai to attend a friend's wedding, which he told his Instagram followers would be the "best wedding ever."
Eleven months later, the 21-year-old has yet to return home to Canada after being swept up in Beijing's spreading anticorruption investigation, which has already implicated dozens of officials in China and reached into the operations of its state-run enterprises abroad.
Mr. Jia told friends in a Facebook post in January that he has been unable to leave China after being placed on a "no fly/exit list" due to an investigation into his uncle, a "very powerful and high ranking politician."
That uncle is one of the Communist Party's most senior figures: Zhou Yongkang, according to several people familiar with the matter. Mr. Zhou, a former domestic security chief who once ran China National Petroleum Corp., is being investigated for "serious disciplinary violations," according to China's state media.
The Wall Street Journal earlier this year found that Mr. Zhou's family members and friends forged ties with CNPC and amassed holdings in the petroleum, investment and media sectors worth tens of millions of dollars. State media has said the state-run oil company's subsidiaries are being probed for embezzlement and inspected for evidence of "private coffers."
The politically sensitive case of Mr. Zhou remains in the hands of the Communist Party's internal investigation arm, officials have said. He is widely expected to eventually be removed from the party and prosecuted.
The travel curbs placed on Mr. Jia provide a glimpse into the far-reaching impact of Beijing's probe and his situation offers a window into the privileged lives of relatives of high-ranking officials abroad.
Chinese authorities have declined to comment on Mr. Jia. Canada's Department of Foreign Affairs said it hadn't received a request for consular assistance.
His inability to leave comes at a time when relations between Ottawa and Beijing have grown increasingly tense. A Canadian couple in August was detained in China and accused of spying, and in late 2012 Ottawa made it harder for state-owned enterprises to buy Canadian oil assets, a once favored destination for Chinese money.
Friends say that Mr. Jia is a Canadian citizen, though that could not be confirmed independently. He is the son of Margaret Jia, who recently left her job as head of the Canadian subsidiary of CNPC amid a shakeup. Ms. Jia is a sister-in-law of Mr. Zhou, according to people familiar with the matter.
After a decade as a high-profile player in Calgary's energy patch, Ms. Jia, who declined to comment, has all but dropped from view, according to multiple people who know her.
Reached in China in August, Mr. Jia didn't respond to questions. Since being contacted Mr. Jia has canceled various social media accounts. Neither Mr. Jia nor Ms. Jia have been accused of wrongdoing.
In his Facebook message Mr. Jia told his friends not to tell others of his predicament because it could "jeopardize" his chances of getting home.
"I don't know what happened, but because of my relation with (my uncle) I cannot leave the country until its being resolved," he wrote, according to a copy of the message seen by The Wall Street Journal.
In his Facebook message, Mr. Jia said: "I didn't do anything wrong, otherwise I'd be detained right now."
He and his mother arrived in Canada about a decade ago, according to people who know the family. His mother's connections to China's state energy companies made her a high-profile player in Calgary, able to command meetings with Canadian lawmakers on short notice.
Her son led a lifestyle not dissimilar from that of many affluent young Canadians, attending hip-hop concerts, watching hockey and taking golfing vacations in Costa Rica, according to photographs that he posted on Instagram, the photo-sharing application.
But even in the affluent part of oil-rich Calgary where he lived, Mr. Jia stood out as wealthy, former classmates say.
By his late teens, Mr. Jia was living in his own house, according to friends. For high-school graduation, he was given a Camaro, with the personalized license plate TEE RAW, by his mother, whose Range Rover he also drove, according to friends and his own photographs. Mr. Jia had a taste for designer clothes, photographing himself in expensive suits, and toting a Louis Vuitton wallet inscribed with O.M.G.s.
Mr. Jia followed his mother into the oil industry while studying for a business degree. According to regulatory filings, Mr. Jia worked as a business development associate at State Resources Investment Corp., a subsidiary of Canada Capital Energy Corp., a Calgary-based oil producer.
Friends describe Mr. Jia as a sociable and generous man who throws birthday parties for others, picking up the tab.
"He's a little bit of a legend," said Kristen Mason, a former high-school friend in Calgary. "Backstage passes, driving cool cars and traveling a lot, he's got a neat life for a young kid."
In January that lifestyle was placed on hold. Friends said that Mr. Jia had told them that he would be in China for a few weeks. Since arriving in Shanghai on Jan. 17, he has sent few messages.
"It was a weird feeling, because we didn't know what was going on," said another friend from Calgary.
In his January Facebook message to friends, Mr. Jia said that relatives had got him a job working in a real estate company. "This is the first time in my life where I feel completely lost," he said.
Access Investor Kit for Facebook, Inc.