The US recording industry continued its legal assault against individuals accused of sharing copyright music, filing 532 more lawsuits against peer-to-peer (P-to-P) network users on Tuesday, including 89 against individuals using university networks.

The move follows 532 lawsuits that the Recording Industry Association of America (RIAA) filed against individuals in January and 531 in February.

The so-called "John Doe" suits are part of the industry's latest campaign against online piracy, targeting individual file sharers. The individuals' names are not known and they are identified only by the IP (Internet Protocol) address of the computer sharing the files.

It's important for everyone to understand that "no one is immune" from the consequences of sharing music files on P-to-P networks, RIAA President Cary Sherman said in a statement on Tuesday. The RIAA went on to say that lawsuits remain a key component of the music industry's efforts to protect its rights.

The latest round of suits took aim at university network users, who are believed to engage in a higher level of online piracy, according to the RIAA. The suits were filed against 89 individuals using university networks in Arizona, California, Colorado, Indiana, Maryland, Michigan, New York, Pennsylvania, Tennessee, Washington DC and Wisconsin. The remaining 443 suits were file sharers using commercial ISPs, the RIAA said.

The industry group also said that the suits filed against individual users in January are progressing. All four courts involved granted the RIAA's preliminary request to issue subpoenas to ISPs to reveal the identities of users accused of piracy. However, in the February round of suits, two courts delayed the RIAA's progress. A Florida court has requested an additional briefing and a Philadelphia court issued a decision that the group had to file individual complaints for each file sharer. The RIAA is asking the court to reconsider its decision, it said.

The recording industry has cited support for its subpoena campaign, saying that the public supports the legal efforts by a "two-to-one margin," according to a poll taken by Peter D Hart Research Associates in March, but opposition to the moves have been vocal.

Last month, for instance, a New Jersey woman filed a lawsuit against the group under antiracketeering statues, charging the RIAA with using scare tactics to extort money from the individuals it sues.

The group's website has also become a target for opposition. It has been repeatedly defaced over the last year or so, with hackers even posting links to illegal music downloads on it, and was taken down earlier this week, believed to be a victim of the latest variant of the Mydoom virus.

The group appears unfazed by the opposition, however, saying that the lawsuits are helping raise awareness among Internet users that it is not right to swap copyright music online.

Lawsuits are part of a larger strategy to move file sharers to legitimate online services, the group said.