By Edward Chaykovsky

According to a report by CBS Affiliate KLAS-TV - Manny Pacquiao, Bob Arum, Top Rank Inc., Michael Koncz, Todd Duboef and possible unknown defendants are being named in a lawsuit filed in U.S. District Court in Las Vegas on Tuesday morning.

The lawsuit, filed on behalf of Staphane Vanel and Kami Rahbaran who live in Clark County, is seeking damages because Pacquiao failed to disclose his shoulder injury before Saturday's fight with Floyd Mayweather Jr. They are looking for $5 million in damages.

According to the lawsuit papers - "the plaintiffs relied on misrepresentations and non-disclosures when purchasing tickets or pay-per-view showings and wagering on the Mayweather-Pacquiao fight."

Similar lawsuits are bound to pop up and other plaintiffs may join the lawsuit in Las Vegas. The arena gate generated more than $70 million and a record number of bets were made on the fight.

Pacquiao is already under fire for entering the fight with the pre-existing right shoulder injury and not disclosing that information to the Nevada State Athletic Commission.

The NSAC is going to conduct an investigation as to why Pacquiao and his team failed to disclose the injury on the pre-fight questionnaire that was completed at the weigh-in. The injury was revealed at the post fight press conference following the fight.

Pacquiao, who suffered the injury in early April, is having shoulder surgery to repair a torn rotator cuff. The surgery could keep him out for the rest of the year.