Applications by tens of thousands of mainland millionaires flooded Canada's consulate in Hong Kong and overwhelmed the country's investor immigrant programme, an investigation by the South China Morning Post has revealed. Canadian immigration department spreadsheets obtained by the Post show how the huge number of applications forced the government in Ottawa to freeze the world's most popular wealth-based migration scheme. One document, dated January 8 last year, showed there was a backlog of 53,580 Hong Kong-based applications for Canadian federal investor visas. That represented more than 70 per cent of the global backlog. And attempts by Ottawa in 2010 to tighten access to the coveted visas by doubling the wealth criteria had the effect of increasing Chinese domination. In 2011, applications sent to the Hong Kong consulate made up 86 per cent of the global total. Analysis of arrival data suggests that about 99 per cent of applications in Hong Kong were lodged by mainlanders. Under the scheme's current limits, applicants worth at least C$1.6 million (HK$11.2 million) receive residency if they "invest" C$800,000 in the form of a five-year interest-free loan to Canada. The applications in the Hong Kong consulate's queue in January last year represented potential "investment" of C$7.5 billion. The queue was revealed when Ottawa halted new applications to deal with the backlog in 2012. What was not revealed was that the vast majority were applications by mainland Chinese which swamped a single consular office in Hong Kong. Vancouver immigration lawyer Richard Kurland obtained the spreadsheets after making freedom of information requests, then shared them with the Post. He said: "The scheme has not been handled properly. The programme is dramatically underpriced." The spreadsheets do not distinguish between mainlanders and Hongkongers. But the Post's analysis of provincial arrival data suggests nearly all applications pending in Hong Kong were lodged by mainlanders. This was confirmed by internal Canadian immigration data. In British Columbia, preferred destination of most Chinese investors, mainland arrivals outstripped those of Hongkongers by 95 to one. Yet few applications were lodged in Beijing - only 252 from 2009 to 2011, compared to 63,796 in Hong Kong. Former Canadian ambassador David Mulroney, who served in Beijing from 2009 to 2012, said he was aware at the time of the huge number of applications in Hong Kong compared to those in Beijing, but could not explain the disparity. "There might have been a technical reason," he said. There were 3,643 investor visa approvals worldwide in 2012. The investigation shows applications received in Hong Kong soared from 520 in 2002 to 34,427 in 2010 - more than 81 per cent of the world total. The figure fell in 2011 as the rise in the wealth criteria took full effect, but still exceeded the processing capacity. Canada's programme was by far the most popular such scheme among rich Chinese. By 2010, applications at the Hong Kong consulate surpassed the combined number received for investor migration schemes run by the US, the UK and Australia.