WASHINGTON -- The US Secret Service fatally shot a man near the White House on Saturday after he approached a security checkpoint and opened fire on officers, according to US media.

The gunshots prompted a lockdown at the White House. A bystander was struck by gunfire and was reportedly in critical condition.

The suspect, who later died in a hospital, was described by US media reports as an "emotionally disturbed person."

The incident occurred near the intersection of Pennsylvania Avenue and 17th Street Northwest, just outside the White House complex.

ABC News' White House correspondent Selina Wang said: "I was in the middle of taping on my iPhone for a social video from the White House North Lawn when we heard the shots. It sounded like dozens of gunshots. We were told to sprint to the press briefing room where we are holding now."