White House Intruder, Secret Service Turned Him Away Hours Before

The White House intruder who jumped a fence, lingered on the grounds, hid behind a pillar and even tried a doorknob had gone right up to the Secret Service hours before and declared his desire to get inside the President's home ... TMZ has learned.

Sources who have been fully briefed tell us, at around 6 PM on March 10th, Jonathan Tuan-Anh went to a security gate at the White House and told Secret Service agents he wanted to get inside. He was turned away but returned and achieved his goal just after 11 PM.

Some members of Congress are outraged, one telling us it's beyond comprehension the intruder was not on the radar of the Secret Service when he jumped the fence. The member notes it was a cold evening ... and after coming face-to-face with Secret Service he showed up again and no one noticed.

We're told the intruder may have actually hung around 1600 Pennsylvania Ave. during the evening, before jumping 2 fences and going undetected for nearly 20 minutes. The Secret Service says Tuan-Anh was there for 16 minutes, but we're told it was several minutes longer.

President Trump was in the White House at the time of the intrusion, yet we're told he wasn't told the intrusion was the result of a massive screw-up. The next day Trump actually praised the Secret Service, in the dark as to what actually went down.

The intruder was carrying mace when he was finally apprehended.