On Memorial Day (Monday, May 30, 2016), The White House went on a partial lockdown after a woman threw a metal object over the fence.

“An individual threw a metal object over the north fence line at the White House. Secret Service Uniformed Division officers immediately apprehended the individual without incident. All protective sweeps of the metal object were met with negative results,” spokesman Shawn Holtzclaw said in an emailed statement.

All of this happened around 12:15 PM, and the Secret Service did not identify the person, although a witness reported to see a woman placed in handcuffs.

The north side of the White House was put on a lockdown on Monday, which was during the holiday when President Barack Obama was home.

Reporters were not allowed to leave the White House through the northwest gate and flashing lights from emergency responders were seen nearby. A local news radio station WTOP said that one person was in custody, after speaking with a federal law enforcement official.

It is common for officers to report immediately to these types of calls regarding the White House and the President in order to check the grounds and make sure that nothing dangerous had been thrown over the fence. Robert Hoback, a Secret Service spokesman said that the sweep results were negative.

As for Obama? He had visited the Arlington Cemetery earlier that day as part of the annual tribute for armed services members.

Since then, the lockdown has been lifted.

This is also not the first time this year that the White House had been on lockdown. In late March of this year, the White House and the U.S. Capitol were on lockdown, after the Capitol Police had shot a man who pulled out a weapon at a Capitol checkpoint. The building was re-opened about an hour later, but the Visitors Center had remained closed until the incident had been fully investigated.

“We do believe this is an act of a single person who has frequented the Capitol grounds before and there is not reason to believe that this is anything more than a criminal act,” Capitol Chief of Police Matthew R. Verdersosa said.

Lesson to take away from all of this? When dealing with the White House and its security, don’t.

(Photo Credit: BRENDAN SMIALOWSKI/AFP/Getty Images)