A man who appears to be the person who left a gift-wrapped box of horse manure outside the home of U.S. Treasury Secretary Steve Mnuchin on Saturday spoke with AL.com via phone late Sunday evening, calling the incident an "act of political theater."

L.A. psychologist Robby Strong provided AL.com with convincing evidence that he is the man behind the now-infamous incident, which attracted the LAPD's bomb squad and other law enforcement personnel to Mnuchin's home in the city's Bel Air neighborhood.

He defended his decision to drop the box of manure - which he says he got from a horse-owning friend - off at Mnuchin's house as a "prank" aimed at raising the awareness of Americans about the idea that "Republicans have done nothing for the American worker" and other political topics.

"The thing I live by is a rule of transparency and I was exercising my First Amendment rights," Strong told AL.com. "A few years ago when [a Supreme Court ruling] said that corporations are persons and money equals free speech, that is so absurd and my rule of thumb is now that if corporations are free speech, then so is horses***t."

At 12:22 p.m. PST Saturday, Strong posted three pictures to Facebook, one of which depicts himself posing with a shovel next to a gift-wrapped box, and another of which shows the box full of what appears to be fecal matter.

They were accompanied by a message that reads in part as follows: "I need someone to ride along and document my Secret Santa project. I'm going to hand deliver boxes of horse s**t to Steve Mnuchin over in Beverly Hills."

Robby Strong posted this photo of a gift-wrapped box filled with what appears to be manure on Facebook Saturday.

Strong told AL.com that he delivered one box of manure to a home Mnuchin owns in Beverly Hills, and another to the home in Bel Air that led to the LAPD sending out its bomb squad.

Strong posted several more photos to Facebook on Saturday between 4:30 and 4:45 p.m. PST, one of which depicted a letter to Mnuchin and another of which showed a gift-wrapped box sitting in front of a palatial house.

"Mrs. (sic) Mnuchin & Trump, We're returning the 'gift' of the Christmas tax bill. It's bulls**t," the letter states. "Warmest wishes, The American People. P.S. - Kiss Donald for me."

Robby Strong posted this photo to Facebook about 50 minutes before the LAPD reportedly received a complaint Saturday evening about a suspicious package outside U.S. Secretary of Treasury Steve Mnuchin's house. (Facebook / Robby Strong)

The LAPD was not notified about a suspicious package at Mnuchin's house until about 5:30 PST Saturday, according to the New York Daily News. Late Sunday night, the LAPD did not answer a call to the media phone number listed on its website.

Strong, who is from Kentucky but now lives in Los Angeles, claims that agents with the U.S. Secret Service showed up at his L.A. home and interviewed him on Sunday, but that they did not arrest him.

"I just got interviewed by the Secret Service and I've now joined some of my heroes like Timothy Leary and Martin Luther King," he told AL.com. "[The agents] just showed up in my yard."

A man who answered the Secret Service's national media hotline late Sunday evening said, "you're calling our after-hours public response desk and i have no information." He directed inquiries to an email address for on-duty personnel, to which an email went unanswered late Sunday night.

Strong downplayed any questions about whether his self-described prank could have alarmed Mnuchin or his family or caused a dangerous situation.

"It was a gift-wrapped package of poo, something a frat boy may do to another frat boy," he said. "I was hoping to meet [Mnuchin.] I wanted to ring the door and hand it to him myself."

Strong said that because there are restrictions on mailing waste materials like manure, he instead opted to personally go to Mnuchin's home and leave it outside.

"I kind of dodged that whole issue. Is there a law that you can't drop off a box of poo? Not really," he explained.

Strong said his end goal is to inspire people to commit more potent acts of political advocacy.

"The fact that [Republicans] can be so brazen and act with such impunity tells me that we have to be more brazen with our activism and maybe a bit more aggressive," he said.