The White House was placed on lockdown early Monday afternoon after an individual threw a metal object over the north fence along Pennsylvania Avenue, the U.S. Secret Service confirmed to The Daily Beast.

The individual was detained and taken into custody immediately without incident, the Secret Service said. D.C. Fire Department trucks and hazerdous material response units were at the scene, according to eyewitnesses. Protective test results of the metal object thrown over the fence came back negative.

President Obama had reportedly just arrived back on the property after attending Memorial Day services at Arlington National Cemetery.

— Andrew Desiderio