The White House was placed on lockdown today after reports of a suspicious package.
A Secret Service official said security breach on the north side of the White House site occurred on the Memorial Day holiday while President Barack Obama was home.
It is reported an object was thrown over the north fence along Pennsylvania Avenue, Washington DC.
Reporters were not allowed to leave the White House compound through its northwest gate and flashing lights from emergency responders could be seen nearby.
The Secret Service official said hazardous material checks were being made.
Local news radio station WTOP reported a federal law enforcement official said one person had been arrested.
Earlier in the day, President Obama had visited Arlington Cemetery as part of the annual commemoration for armed services members.
