WASHINGTON (AP) -- A marathon and relay race in the nation's capital is causing significant road closures downtown.

The SunTrust Rock `n' Roll USA Marathon and the CareFirst Blue Cross/BlueShield National Half Marathon and Relay Races are scheduled for Saturday in the District of Columbia.

Some roads are expected to be closed as early as 3 a.m. Saturday, though the races won't begin until about 8 a.m. All
closed roads are expected to be reopened at around 2:30 p.m.

The marathons will form at 19th and C Street, NE.

Traffic delays are expected during the races.

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