The New York killer of two firemen left a note on his plan to "do what I like doing best, killing people".
More top news
Over 40,000 people picked up their packs to take part in the annual marathon in the capital.
The country's voters are concerned about security, the economy, and the 10% unemployment rate.
A pregnant woman and a man suffered "severe discomfort" after someone threw bleach at them from a passing car, hitting them in the eyes.