Customs officers have arrested 28 people and seized more than 100 catties of fake dried abalone slices worth $30,000.

They raided 31 dried-seafood shops in the past week, arresting 22 men and six women, aged 30 to 59.

Officers tested abalone slices with trade descriptions stating they were Australian, Japanese, American or South African abalone in December, and found 31 samples were actually conches.

The seized items were priced from $128 to $560 per catty while genuine dried abalone can cost more than $10,000 per catty.

The Customs & Excise Department urged consumers to buy dried seafood from reputable shops.