HONG KONG, May 7  -- Hong Kong Customs has foiled a suspected smuggling attempt and seized about 4 million HK dollars (about 520,000 U.S. dollars) worth of unmanifested electronic products from two sampans, it said here Thursday.

The customs officers discovered two sampans, each loaded with 23 cartons of unmanifested goods on board, in a small river at Tai Sang Wai, Yuen Long early Wednesday.

The officers seized the 46 cartons of goods containing a total of about 5,000 used smartphones, 200 used tablet computers and 10, 000 pieces of electronic parts at the scene.

The investigation is continuing.

Under Hong Kong's Import and Export Ordinance, smuggling is a serious offence. The maximum penalty is a fine of 2 million HK dollars and imprisonment for seven years.