Confusion over the identity of the mystery buyer who paid $1.09 billion for a Hunghom commercial site at Monday's government auction deepened yesterday, with Li Ka-shing's Cheung Kong admitting it was somehow involved. But the SAR's biggest developer would not reveal if it was behind the purchase by Sino China Enterprises, a previously unknown private shelf company. Cheung Kong spokeswoman Wendy Tong Barnes said: 'It is quite a complicated matter, we cannot deny that we have no involvement but presently I cannot give you any details. 'Once the situation clears up, I will let you know,' she said. Analysts speculated over the meaning of Cheung Kong's statement. Some suggested that Sino China had acted on its behalf, and others wondered whether Sino China was an independent entity in which Cheung Kong sought a stake. Others thought the venture might involve other partners or that Cheung Kong had delayed disclosure of its engagement to keep the price down.