The investigation into Donald Trump’s attempted assassin have been slowed down by improvised explosives rigged across his property, senior law enforcement sources with direct knowledge of the search told The Post.

Explosives were found in 20-year-old Thomas Crooks’ car as well as his home, sources said.

The explosives were described as having “varying” levels of sophistication, though it is unclear exactly what they consist of.

Investigators were forced to tread lightly after uncovering the explosives in Crooks’ property.

No motive has been been given for the assassination attempt on Trump.

Crooks donated $15 to a pro-Democrat PAC as a 17-year-old in 2021, but then registered to vote as a Republican when he turned 18.

The streets around his home in Bethel Park, Pennsylvania, were blocked off by law enforcement early Sunday morning, with neighbors telling The Post they saw bomb squads arrive at the home around 1 a.m.

“I went down there and spoke to the county bomb squad at 1:06 a.m. He said he was about to go into the house,” the neighbor said.

“I didn’t know the guy. No one in this neighborhood really talks to each other.”

Crooks unloaded about eight shots from an AR-style rifle as the former president spoke to a rally just after 6:10 p.m. in Butler Park — around an hour north of his home in the suburb south of Pittsburgh.

He grazed Trump’s ear, killed one bystander in the crowd, and critically wounded two others. Secret Service snipers returned fire and killed him.

Crooks was believed to have crawled along the roof of a manufacturing plant about 130 yards from the stage where Trump spoke.

His car was found nearby.

Exactly why he carried out the shooting is unclear.

His father told CNN he was trying to figure out “what the hell is going on” after his son began being identified as the suspected assassin, adding that he was going to “wait until I talk to law enforcement” to speak on the shooting.

The gun Crooks allegedly used was purchased by his father, according to reports.

Former high-school classmate Jason Kohler described Crooks as a “relentlessly” bullied loner, known for wearing hunting outfits to class, according to KDKA.

“He didn’t seem like really weird or anything. I would have pegged him as a Republican,” a former classmate told The Post.

Another said he had “a few friends” but “didn’t have a full friend group” and that he frequently played video games on his laptop at school.

“He never outwardly spoke about his political views or how much he hated Trump or anything,” Bethel Park High School classmate Sarah D’Angelo told the Wall Street Journal.

Crooks graduated from the school in 2022.