Samsung Electronics said it has filed a second patent lawsuit against Apple in South Korea, alleging infringement of tablet and smartphone technology.
Samsung said today that the lawsuit filed earlier this week in Seoul alleges that Apple's iPhone 4S and iPad 2 infringe three of Samsung's patents.
Samsung's lawsuit comes as Apple unveils its new iPad in the United States this week.
The technology giants are engaged in a legal battle in many countries.
Apple sued Samsung in the United States in April last year and Samsung sued Apple in South Korea in the same month.
Apple claims Samsung's Galaxy tablets and smartphones "slavishly" copied its iPhone and iPad models.