US Secret Service members block Pennsylvania Avenue in front of the White House in Washington during a security lock down, US, May 30, 2016. [Photo/Agencies]

WASHINGTON - The White House has resumed normal operations after being partly on lockdown due to a suspicious package thrown over its north fence earlier on Monday, a NBC news report said.

A woman allegedly throwing the package was immediately taken into custody and currently under the investigation, local reports said.

The incident happened at around 12:15 pm eastern time, a few minutes after US President Barack Obama arrived at the White House following a visit to Arlington National Cemetery where he attended a Memorial Day service and placed a wreath on the Tomb of the Unknowns.

This is the second time the White House has been on lockdown this month. On May 20, a man brandishing a weapon was shot down by US Secret Service near an outer perimeter checkpoint of the White House, leaving the compound closed for nearly one hour.