French Internet providers have begun sending email warnings to users caught illegally dowloading films and music under a new anti-piracy law, authorities said on Monday.

The High Authority for Dissemination of Works and Protection of Rights on the Internet (Hadopi) said the first warning emails had been sent on Friday warning suspects that they will face legal action if the piracy continues.

The Internet piracy watchdog Hadopi, set up in 2009 to fight piracy and promote legal online sales, catches users by obtaining the IP number that identifies individual computers on a network.

"Attention, your internet connection has been used to commit legally-noted acts that could constitute a breach of the law," begins the lengthy email that the suspects then receive.

If the piracy recurs within six months, the Internet user receives a second email, followed by a registered letter. After a third infraction, their Internet connection can be cut for up to a year and a fine imposed.

The specialist IT journal PcInpact reported that the first warnings had been sent to subscribers of two major internet service providers, Numericable and Bouygues Telecom, while SFR and Orange were due to follow this week.

The law is being touted as an example for other countries and the best way to protect artists' income, but critics see the threat of having Internet connections cut as a breach of human rights.

"Instead of developing legal options as promised, Hadopi is going straight to slapping people down," said Edouard Barreiro of the consumers' association UFC-Que Choisir.