Donald Trump shooter's movements in the 48 hours leading up to the attempted assassination

The eyes of the world are on the FBI this week as agents try to piece together a motive behind the attempted assassination of Donald Trump on Saturday.

Investigators seem to be stumped as to how 20-year-old Thomas Matthew Crooks ended up on a roof in Butler, Pennsylvania shooting at the former president of the United States. They have, finally, been able to get into his phone and are continuing to interviews but so far, there is no answer.

What they have been trying to map out are his exact movements in the lead up to the historic event . Here's what we know so far .

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Crooks, who was killed by the Secret Service at the scene, was from a suburb of Pittsburgh about an hour away from Butler. He was a registered Republican but made a small, $15 donation to a Democratic group as a 17-year-old.

He planned to attend Robert Morris University this autumn and has been described as "quiet" and reserved. Some of his old classmates said they were "shocked" when they learned he was behind the shooting.

His employer, Bethel Park Skilled Nursing and Rehabilitation Center, had a similar response.

Crooks was a member of a gun club with a shooting range, Clairton Sportsmen’s Club, which he visited the morning before Trump's rally in Butler, according to a source that spoke to CNN.

On Saturday morning, he went to a Home Depot store and purchased a ladder. He then bought 50 rounds of ammunition at a local gun shop.

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Later that day, he drove to Butler and used that ladder to scale a building near the rally and shoot at Trump multiple times with an AR-15 style rifle that belonged to his father.

According to CNN's source, Crooks also had a box of explosives in his car, parked nearby, and a remote control detonator on his body.

The rifle was legally owned, officials said, and it is being investigated wether or not Crooks took the firearm from his father without him knowing.

His plan for the explosives is still to be determined as is his political stance, a motive and much, much more.

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