The 81-year-old woman got to know a 59-year-old man through a friend earlier this year, and the man allegedly stole the deed of assignment for her Tai Kok Tsui flat.

Another 26-year-old used the stolen document to borrow HK$6 million from a money lender, and even brought with him an old woman pretending to be the rightful flat owner. Both men were arrested last Friday.

Financial Intelligence and Investigation Bureau's acting chief inspector Sung Ka-wai said police busted the scam during a money laundering investigation.

Officers found a suspicious transaction involving the 26-year-old suspect. He deposited a cheque worth HK$5.99 million on October 28, and told the bank that he wanted to take the amount in cash the next day.

The big amount raised alarms and officers started tracing where he got the money from. They found that it was a mortgage made based on a Tai Kok Tsui property owned by a 81-year-old woman.

When police approached the property owner, she said she did not apply for a mortgage at all. Further investigation found that the woman got to know a 59-year-old man who asked her where she stores important documents earlier this year. She did not realize the deed of assignment was missing until the police probe.

Knowing the 26-year-old suspect would take the borrowed cash from the bank, officers ambushed him last Friday and found the money in his backpack. They also seized a fake HK identity card with the 81-year-old woman's name on it. He was arrested and charged for conspiracy to defraud.

The other 59-year-old man, believed to be an accomplice, was also arrested on Friday. He was detained for investigations.

Police called upon the public not to tell strangers about where they put valuables and important documents.