A man jumped onto a bike rack to try and make an effort to climb over the fence to get onto the white house grounds. However, he had no weapon, and was only carrying a letter for Trump. Secret Service acted quickly and he is currently under going interrogation for what his intentions were. Even though Trump wasn't in the house at this time, serious measures have been taken. This incident was following behind another similar situation that happened on March 11, where a man jumped the fence and had mace and a letter for Trump. He was walking around on the white house grounds and trying doors for seventeen minutes before any action was taken place to stop him, at this time Trump was in the white house. House Oversight Chairman Jason Chaffetz stated, "That's why we spend billions of dollars on personnel and dogs and technologies and fences and undercover people and video surveillance," he said. "And yet the person is able to get up close to the White House and spend 17 minutes before he's apprehended. That's unbelievable." Both of the people in these two incidents are or have been interrogated and measures are being taken to ensure similar situations don't occur again.
http://www.cnn.com/2017/03/18/politics/white-house-jumper/index.html
http://www.cnn.com/2017/03/18/politics/white-house-jumper/index.html