A Florida teen allegedly set his girlfriend’s house on fire while she and her parents were inside. But when confronted by detectives, he claimed a “random black guy” did it.

Cops say Jose Bernardo Rosas Madrigal doused the Polk City home with lighter fluid—days after he scoured Google for “how to burn a brick house down,” and threatened to kill his sweetheart over Snapchat.

The 19-year-old even used the liquid fuel to draw a heart on a fence near his girlfriend’s bedroom window, the Polk County Sheriff’s Office says.

After Madrigal ignited the family’s front yard, he drove past the house to see his handiwork, authorities allege.

James Scott, the father of the girlfriend, says his residence avoided damage but that parts of his yard went up in flames. “We were very lucky. We caught it in time before it blew up,” Scott told The Daily Beast.

“I thank God because God was on our side,” Scott added. “If it would have gone 5 or 10 more minutes, the car would have blew up. My house would have been on fire. He could have killed us.”

Madrigal faces three counts of attempted first-degree homicide and one count of first-degree arson. He is also charged with possession of liquor by a person under 21.

Messages left for Madrigal’s public defender were not returned. He remains in Polk County jail on a $60,000 bond, records show.

“He planned this in advance. He Googled how to burn the house, he mixed the combination and poof, he set it on fire. And poof, we put him in jail,” said Polk County Sheriff Grady Judd in a statement to The Daily Beast.

The Scott family reported the blaze at 7:30 p.m. on the day after Thanksgiving.

According to an arrest affidavit, the girlfriend received “several Snapchat [messages] which had threats of burning down her home.”

Scott told The Daily Beast his daughter had recently requested some space from Madrigal, whom he described as “controlling.” Madrigal and the girl, who are high schoolers, had been dating for a year, Scott said.

Recently, the girl began receiving death threats on Snapchat from a bogus account, and those warnings continued even after the blaze, Scott said. (Police believe Madrigal is behind the social media threats.)

But when deputies began investigating the messages, they soon focused on Madrigal.

The teen told investigators that he was at his mother’s Auburndale home, 25 minutes away, when the fire broke out, the affidavit says.

Yet a neighbor’s surveillance footage showed Madrigal’s truck arrive at the home minutes before the victims dialed 911, police say.

When confronted with the footage, Madrigal told a detective that “he was in the neighborhood driving by [his girlfriend’s] house trying to check on her,” because they’d had a spat earlier in the day, the affidavit states.

Madrigal said he drove past the house three times, and on the third, he saw the yard burning, police say. The high schooler allegedly told cops he didn’t know what to do, so he took off.

One neighbor told News Channel 8 that residents helped extinguish the flames. “There was liquid everywhere,” Margaret Elkins told the Tampa station.

Elkins claimed Madrigal appeared at the scene minutes later and said something that gave her chills. “Usually the one that does it comes back to see what all the excitement is about,” Madrigal said, according to Elkins.

The teen would later tell investigators that he saw a “random black guy” light the flames before running off, the affidavit alleges.

Police say they searched Madrigal’s phone and discovered Google searches made just before the fire, including, “can you start charcoal with gasoline house on fire,” “how to burn a brick house down,” and “does liquor have alcohol to turn on fire.”

Inside Madrigal’s truck was a half-full bottle of Pinnacle Vodka, police say.

When asked about his search history, Madrigal allegedly claimed his brother was the one who started the blaze and that he helped him carry out the deed.

According to the affidavit, Madrigal told detectives that he knew his girlfriend and her mother were in her bedroom doing homework, and that her father was home, too.

Scott told The Daily Beast he was devastated by Madrigal’s alleged crime.

“We heard a boom outside, and I never thought anything of it. Push came to shove, and my wife says, ‘James, honey, you need to go and check it out,’” Scott recalls.

“She opened the door, and it just smelled like some kind of gas or toxic fume,” he added. “You could smell it from a block down the road.”

Scott went outside to find his canoe and front yard in flames. He said he quickly put the fire out before it spread.

Madrigal had a troubled home life, Scott said. Wanting to help the teenager, Scott arranged for him to move in with Scott’s mother, where his daughter also stayed sometimes.

Scott says that the night before the fire, his mother told Madrigal he needed to find somewhere else to live.

Madrigal was five months away from graduating high school. “I hate to see the kid go to prison and ruin his whole life,” Scott said.

“We feel bad in a way,” the father added. “I feel sorry for him. We don’t even really know what to do. We’re stunned.

“I guess it’s a love gone bad or something.”