Seoul: North Korea has started firing drills near a disputed sea border with North Korea, South Korea`s military said on Tuesday, after it notified the South earlier of two areas near populated islands where it would conduct the exercise.  The firing began at about 2 pm local time (0500 GMT) and no rounds appeared to have landed south of the live disputed Northern Limit Line border, a military official said. A similar artillery drill by the North in March resulted in more than 100 shots landing in seas south of the border and prompting South Korea to fire hundreds of rounds back into the North`s water.