Cops investigating a Long Island teen over a swastika scrawled in his high school found homemade bombs in his home — and busted his dad for buying the dangerous chemicals used to make them, according to authorities.

The 15-year-old student allegedly drew the hate symbol at Syosset High School, prompting Nassau County police to visit his home at around 1:30 p.m. Wednesday, where they found “several chemicals” that had been “combined to make explosive materials,” the department said.

The teen was arrested alongside his father, Francisco Sanles, 48, who on “multiple occasions paid for the purchase of the various chemicals,” the department said.

Police shut down Patricia Lane, a quiet, residential street, for much of the day, as video showed several unknown chemicals being removed from the home and lined up in the front yard, ABC 7 reported.

The bomb squad said the chemicals were too hazardous to move as they had been combined to create explosives and destroyed them on site.

Neighboring houses shook, and a loud boom was heard as the unidentified materials were safely exploded.

Sanles senior was charged with two counts of criminal possession of a weapon, two counts of criminal facilitation, two counts of endangering the welfare of a child, and reckless endangerment.

His son — who was not otherwise identified bacause of his age — was charged with two counts of criminal possession of a weapon, criminal mischief, aggravated harassment and making graffiti.

Both are due in court separately on Thursday.

The FBI helped with Wednesday’s investigation, but said the case is now in the hands of Nassau County deputies.

The school district sent an email to students and staff on Wednesday night following the incident.

“I am writing to inform you that the District found swastikas and racial epithets above urinals at Syosset High School. The District immediately commenced an investigation and notified the Nassau County Police Department,” the statement read.

“Our investigation identified the person responsible and this is now a criminal matter with an active police investigation. We are cooperating fully with our partners in law enforcement and remain in constant contact with them as their investigation continues,” the statement continued.

“This student will also face serious consequences pursuant to the District’s Code of Conduct. Antisemitism and hate speech have no place in our communities or in our schools,” it went on.