The suspected gunman in the assassination attempt on former US President Donald Trump, Thomas Matthew Crook, was marked as “suspicious” by the  Secret Service about an hour before he took his first shot at Trump, however, he got lost in the crowd, law enforcement officials have told lawmakers, BBC reported.

In two closed briefings to lawmakers on Wednesday, law enforcement officials, including the Secret Service, provided limited updates on security measures and details regarding the individual who fired shots at a Trump rally in Pennsylvania last Saturday.

According to Wyoming Senator John Barrasso, the Secret Service informed them that they had observed the assailant one hour prior to the incident but subsequently lost track of him.

“He was identified as a character of suspicion because [he had] a rangefinder as well as a backpack. And this was over an hour before the shooting actually occurred,” Barrasso told Fox News.

Crooks parents contacted police

Fox News has reported that Crook’s parents had called up the law enforcement, hours before he aimed shots at Trump, concerned for his welfare and saying that he was missing. However, it is unclear if they knew he was in possession of an AR-15 rifle which belonged to his father. Crook’s parents are cooperating with FBI investigators 

Gunman visited site of attack

During the briefings it was also revealed that Thomas Matthew Crook had visited the site of the attack at least once in the days preceding the assassination attempt. He had also searched for symptoms of a depressive disorder on his phone, an official familiar with the briefing told CBS News.

ABC News and several other US outlets have said that the 20-year-old shooter was spotted on the roof of a building 20 minutes before he opened fire at Trump. He was shot dead 26 seconds after he fired. Multiple senators have now demanded the resignation of Secret Service Director Kimberly Cheatle.

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