Myanmar tightened security for a visit by President Lee Myung-bak on Monday, the first by a South Korean leader since an assassination attempt by North Korean commandos nearly 30 years ago.

Lee flew to the capital Naypyitaw to meet with Myanmar President Thein Sein as part of a two-day visit that is expected to strengthen ties between the Asian countries, a statement from Lee's office said.

The South Korean president is the latest dignitary to visit Myanmar as it transitions from a military dictatorship to a fledgling democracy and opens its massive investment potential to the eager international community. The statement said Lee planned to discuss how to increase economic ties and cooperation in energy, development of natural resources and other sectors.

Myanmar state television showed Lee's arrival in Naypyitaw and his welcome by an honor guard at the president's office. It said he met with Thein Sein, along with Myanmar's home minister and ministers of commerce, energy and national planning and other Cabinet members.

Truckloads of riot police were stationed at major intersections in Naypyitaw and around Yangon, where Lee was to visit Tuesday and meet opposition leader Aung San Suu Kyi. Security was particularly tight at the Martyr's Mausoleum, a monument to Suu Kyi's father where then-South Korean President Chun Doo-hwan was nearly killed in 1983.

The bomb blast killed 21 people, 17 of them South Korean, including four Cabinet ministers and the South Korean ambassador to what was then known as Burma. Chun was not hurt because he arrived a few minutes late for a ceremony to pay tribute to Gen. Aung San, the country's slain independence hero.

Three North Korean agents were arrested for the attack. One blew himself up while being arrested, a second was hanged in prison and a third died inside Yangon's infamous Insein Prison in 2008.

After the bombing, Myanmar's then-dictator Ne Win severed diplomatic relations with North Korea, but those ties were restored in 2007. The United States and other nations have expressed concern about Myanmar's relationship with nuclear-armed North Korea.

Arms experts say Myanmar — which faces an arms embargo from many Western states — gets weaponry from the North in defiance of U.N. Security Council resolutions. Some believe there is nuclear cooperation between the two countries, which Myanmar denies.

South Korea is the fourth-largest foreign investor in Myanmar after China, Hong Kong and Thailand with a total investment of $2.67 billion for the 2010-2011 fiscal year, according to the Ministry of National Planning and Economic Development. The biggest share is in the energy sector.