Lee Si-hyung

A special investigation team that is probing allegations surrounding President Lee Myung-bak's now-scrapped retirement complex plan has summoned his son for questioning.

Lee Si-hyung was due to be questioned as early as Thursday to find out whether he violated real estate laws and misused taxpayers' money to purchase a plot of land in Naegok-dong, southern Seoul.

The younger Lee initially wanted to postpone questioning until next month, citing private busines, but he later agreed to the summons.