Customs officers have arrested three women and a man for contravening the Trade Descriptions Ordinance by using aggressive sales tactics.

The Customs & Excise Department received complaint that a woman's credit card was charged without authorisation for another 10-year membership to a fitness centre worth $38,000 on top of the 10-year membership she subscribed to earlier.

The transaction was made when the salesperson collected her credit card and identity card, claiming it was for discount purposes.

Although the victim refused the new membership, staff allegedly forced her to sign the credit card receipts, insisting the processed amount could not be cancelled.

One salesperson and three managerial staff of the fitness centre were arrested and have been released on bail.

The department's Group Head of Unfair Trade Practice Investigation, Hui Wai-ming, reminded consumers to refuse to sign any documents if they have no intention to purchase a service.

Consumers should not casually provide an identity card or credit card to any salesperson before making a transactional decision, he added.