The American head of a virtual currency exchange was found dead near a block at Cantonment Close last Wednesday.

The death of Ms Autumn Radtke, 28, chief executive of Singapore-based virtual currency exchange platform First Meta, has been classified as a case of unnatural death.

Police had received a call for help at Cantonment Close at about 7am last Wednesday, where Ms Radtke was found lying motionless. She was later found to be dead by paramedics.

Preliminary investigations suggest that no foul play was suspected, said police. Toxicology tests are being done to determine the cause of her death.

Ms Radtke had joined First Meta in 2012. First Meta is an exchange for digital currencies used in games and virtual worlds, such as Linden dollars from the Second Life online world. It does not trade in bitcoins and is not a bitcoin exchange, but it accepts bitcoins as payment for other virtual currencies.

According to Ms Radtke's profile on LinkedIn, a global online professional network, she was previously director for business development at Xfire, an instant messaging service for gamers, for about a year.

Ms Radtke was also a former Virgin Charter employee, an online flight chartering service owned by the Virgin Group. She worked there for three months in 2008.

"The First Meta team is shocked and saddened by the tragic loss of our friend and CEO Autumn Radtke. Our deepest condolences go out to her family, friends and loved ones. Autumn was an inspiration to all of us and she will be sorely missed." First Meta posted on its website.