BRUSSELS (Reuters) - European Union regulators have opened an investigation into imports of fake coronavirus-related products that are ineffective or even harmful to health, the European anti-fraud office OLAF said on Friday.

Products seized include masks, medical devices, disinfectants, sanitisers and test kits.

Counterfeit masks, including fake ones for children, have been offered online in European Union countries for between five euros ($5.35) and 10 euros each, around three times their normal price.

“On top of being ineffective against the virus, these products also fail to comply with EU standards, potentially damaging our health. For instance, they could provoke a dangerous bacterial contamination,” OLAF said in a statement.

OLAF said the fake products enter Europe through online sales and arrive mainly via postal or courrier services but also via containers with forged certificates, or by being declared as other products. They are then found in normal distribution channels or on the black market.

The EU imposed a 30-day travel ban on all non-essential travel into the bloc on March 17 to fight the spread the coronavirus.