Transcript for Bomb threat, intruder spark White House security scares
Back now with those new concerns about white house security after a bomb threat over the weekend. Our senior white house correspondent Cecilia Vega has new details. Good morning, Cecilia. Reporter: Hey, Mike 8. Good morning to you. President trump is back home here at the white house after a weekend away at mar-a-lago. With new questions after three white house scares in a little over a week. A man driving this car to a secret service checkpoint near the white house on Saturday, allegedly telling an officer there's a bomb in the trunk and saying this is a test as he was taken to the ground. Emergency vehicles swarming the street. No bomb was found. The suspect arrested. Earlier that day another incident at 1600 Pennsylvania avenue, after an intruder jumped over a bike rack barrier along the north fence of the white house. He didn't make it over. Sources tell ABC news he wanted to deliver a letter to someone in the administration. You don't want them to think they can go and deliver a letter to the president by jumping the fence. Reporter: The president was inside the residence last week when secret service found an intruder on white house grounds. Authorities say Jonathan Tran jumped a fence at the treasury department, vaulted another fence around the white house, hiding behind a pillar on white house grounds before he was found and arrested at the south portico. The secret service says Tran was on the grounds for 16 minutes. I thought we had learned some lessons but this is perhaps the worst one I've seen. Reporter: A letter from congressional investigators say Tran may have triggered alarms the secret service ignored and that Tran not only moved an the white house grounds undetected, but may have also attempted to enter the building. He got to the white house literally jiggling the door. Reporter: The series of incidents leading to questions about whether one of the most secure sites in the country is secure enough. A security redesign of the white house fence is in the works, one of the changes to come, raising the fence from 8 feet to more than 13 feet. If having the security where it's at right now isn't working from deterring people from trying then you have to move the security layer further out so they don't even get to that fence. Reporter: And not just the white house, there were also questions about security this weekend at mar-a-lago, take a look. This guest tweeting a photo of himself inside the president's study saying he snuck past secret service to get there. They say it's false that guests are allowed in the area and no one snuck past security this weekend. Thank you, Cecilia. Amy, you have what's coming
This transcript has been automatically generated and may not be 100% accurate.