BRUSSELS, May 16 (Reuters) - Chinese fast-fashion e-commerce retailer Temu was hit with a European Union complaint on Thursday, with pan-European consumers group BEUC saying the PDD Group-owned unit might have breached online content rules.

Under the European Union's Digital Services Act, online marketplaces and intermediaries are required to fight illegal and harmful content as well as counterfeit products on their platforms.

BEUC said it has taken its grievance to the European Commission while 17 of its members in countries including France, Italy and the Netherlands have also filed complaints with their relevant national authorities.

Temu, with 75 million monthly EU users as of March, often failed to provide consumers crucial information about the sellers on its platform and whether their products meet EU product safety requirements, BEUC said.

The complaint said that Temu uses manipulative practices such as dark patterns to get consumers to spend more than they may want.

"Temu is being complacent here because it is breaching the EU's Digital Services Act," BEUC Director General Monique Goyens said in a statement.

"Products sold on marketplaces, whether online or offline, whether they are European, American or Chinese, must be safe and comply with European law if they sell to European consumers." (Reporting by Foo Yun Chee; Editing by Richard Chang)