South Korea is bracing for any possible terror attacks from North Korea, an official said Friday.

"The presidential office of national security is thoroughly in control of every situation related to terror," presidential spokesman Jeong Yeon-guk told reporters.

Still, he declined to comment on whether National Security Adviser Kim Kwan-jin or other South Korean officials are included on North Korea's alleged hit list.

South Korea believes that North Korean leader Kim Jong-un has ordered intensified preparations for terror attacks on South Korea, Kim Sung-woo, chief presidential press secretary, told reporters on Thursday.

The warning came amid heightened tensions on the Korean Peninsula over North Korea's nuclear test and long-range rocket launch in recent weeks.

Police said earlier this week that North Korean hackers sent massive amounts of spam emails to South Korean public organizations last month, the latest in a series of cyberattacks against the South in recent years.

Lee Chul-woo, a lawmaker of the ruling Saenuri Party, said on local radio that North Korea could launch a cyberattack in March or April, citing the North's track record of waging such attacks against South Korea soon after its nuclear tests.

North Korea launched a cyberattack against South Korea in July 2009, two months after its second nuclear test. It also hacked South Korea media organizations in March 2013, a month after its third nuclear test.

North Korea carried out a fourth nuclear test last month, followed by a long-range rocket launch earlier this month.

North Korea also has a track record of staging terror attacks against South Korea in the past few decades, including the 1987 midair bombing of a Korean Air flight that killed all 115 people aboard. (Yonhap)