The White House was briefly put under lockdown around 4 p.m. Friday before being lifted a few minutes later. While the cause is not yet known, Secret Service agents were viewed forcing news crews inside a briefing room, according to ABC News

The lockdown was announced at the same time as a travel/photo lid, which signals that no more news would be coming from President Obama or the White House that day. It occurred almost a month after two consecutive incidents in early May that shut down the White House for several hours each.

The first, on May 6, happened when a car tried to follow a motorcade for Obama's daughters past a security checkpoint. The driver, Matthew Evan Goldstein, 55, was arrested and charged with unlawful entry, although nothing illegal or suspicious was found in his car.

Angela Greiling-Keane, the White House correspondent for Bloomberg Business, and Fred Lucas, the White House correspondent for The Blaze, were the first people to report the lockdown from the briefing room.

The second, on May 8, involved two suspects throwing objects over the north and south fences in the middle of the afternoon. At the time, Obama was in California for fundraisers, according to the Washington Post. Both suspects were quickly put in custody and the objects were cleared.