On Tuesday, the actual date of the anniversary, the government will conduct a memorial service at the national cemetery in Daejeon to remember the 46 sailors who were killed and Warrant Officer Han Joo-ho, who died in a rescue attempt, the Yonhap News Agency reported.
The 1,200-ton Navy corvette carrying 104 service personnel sank near Baengnyeong Island in the Yellow Sea March 26, 2010. A multinational investigation team determined a North Korean torpedo caused the sinking, a finding denied by North Korea.
South Korean President Park Geun-hye was expected call for her country to boost military preparedness against North Korea's possible provocations and to respond firmly.
North Korea recently said in a video it could seize South Korea in three days. It said it would overrun U.S. and South Korean troops and take 150,000 Americans prisoner, the Stars and Stripes reported.
The video ended with a taunt challenging the United States and South Korea to elaborate on various scenarios they run during war games.
"We know why Pentagon authorities have not released any content of their scenarios to the media, and are in fear as well despite their continuous practice through computer simulations of how the U.S.-South Korean combined forces will invade North Korea," the video says.
North Korea has released propaganda videos since the United Nations imposed more sanctions on the country for its recent rocket launch and nuclear test, South Korean officials said.
Frequent targets have been the joint U.S.-South Korea Foal Eagle and Key Resolve military exercises that began this month, the Stars and Stripes said. Key Resolve finished Thursday and Foal Eagle runs until April 30.
In a video posted by Uriminzokkiri -- a North Korea propaganda outlet in China -- soldiers and tanks are shown advancing as bombs and missiles fall on South Korea. A voiceover and text suggest that on the first day of the surprise "pre-emptive" strike, 150,000 Americans living in South Korea would be taken prisoner, the Stars and Stripes said.
As the U.S. and South Korean militaries are devastated, the video said, North Korean soldiers will move into the cities, destroying the infrastructure in the process.