Despite signing a 1953 armistice to end fighting on the Korean peninsula, North and South Korea are theoretically still at war with each other. Relations between the neighboring states are perpetually strained: at the height of a crisis in 1994, Pyongyang threatened to turn Seoul into a "sea of fire." The latest wave of tension on the Korean peninsula began this year on March 26, when a blast hit the ROKS Cheonan, a South Korean naval vessel, while it was stationed off the country's western coast in the Yellow Sea. The explosion split the 1,200-ton warship in two and, of the Cheonan's 104 personnel, 46 went down with the ship.
South Korean officials were hesitant to pin the blame on their aggressive northern neighbor, initially attributing the incident to a stray naval mine left behind from the Korean War. Nearly two months later, an international team of investigators said evidence overwhelmingly pointed to a torpedo fired by a North Korean submarine. North Korea has denied responsibility for the incident, but tensions on the peninsula remain high.