More than 20,000 South Korean iPhone users filed a class action lawsuit Wednesday against US technology giant Apple for alleged privacy violations over the collection of location data, a law firm said.

The suit came after lawyer Kim Hyung-Suk was awarded one million won ($933) in compensation in June, the first such payout by Apple's Korean unit, following an interim order by a court in the southeastern city of Changwon.

Kim has since led online preparations for a class action suit against Apple and its South Korean unit.

"The suit accuses Apple of breaching articles 10 and 17 of the constitution that ensure pursuit of happiness and protection of privacy, and the South Korean law on protection of location data," a spokesman for Kim's firm Miraelaw told AFP.

The suit involves 26,691 people demanding one million won each, he said.

"We... electronically filed a suit seeking compensation from Apple and its South Korean unit for emotional damage caused by illegal location tracking by Apple's iPhone," the law firm added in a statement.

A separate suit involving another 921 people will be filed soon, after they submit the necessary paperwork, it said.

Apple Korea spokesman Steve Park declined to comment.

In his earlier suit, the lawyer claimed his privacy was breached by Apple because it collected location information without his consent.

The court in Changwon issued a compensation order via an expedited process that did not involve extensive deliberations on the merits of the complaint.

Users who bought iPhones before May 1 have joined the class action suit.

Apple in May released updated software for iPhones to fix "bugs" that resulted in location data being unencrypted and stored for up to a year. South Korea has about three million iPhone users.

The Korea Communications Commission (KCC) said in early August it would fine Apple Korea up to three million won over the disputed feature.

The move followed a probe launched by the regulator in April to check if the collection of location data from iPhone users violated privacy rules.

The regulator's decision "cleared a lot of doubts" on whether the popular smartphone's location-tracking feature was against the law, Miraelaw said.

But it will take a long while to hold the first hearings on the case given the time needed for the court and Apple's US headquarters to review related documents, a court official told Yonhap news agency.