A consortium led by Hyundai Motor Co. has offered 10 trillion won ($9.6 billion) for land in Seoul's tony Gangnam district where it will build a new headquarters.

State-owned Korea Electric Power Corp. said Thursday that the consortium outbid Samsung Electronics Co. in an auction for the 79,342 square meter plot in the high-priced area. The consortium consists of Hyundai Motor, Kia Motors Corp. and auto parts maker Hyundai Mobis Co.

Shares of the three companies each plunged nearly 10 percent. The land was valued at 3.3 trillion won.

Hyundai Motor said it will build a super tall tower for its headquarters that will oversee 30 affiliated companies.

South Korea's largest automaker said it will also build auto-themed exhibition halls, hotels and shopping malls in the area.