CEDARHURST, N.Y. (CBSNewYork) – There was a violent rampage in a quiet Long Island neighborhood over the weekend.

Police said a man intentionally set his neighbor’s house on fire, after attacking his own parents. Several people have been forced from their homes, as the suspect sits behind bars, CBS2’s Reena Roy reported Sunday.

Two badly charred homes were boarded up and vacant on quiet 1st Street in Cedarhurst, after flames and thick smoke tore through them early Saturday morning.

“It was very, very scary,” neighbor Judy Capoziello said. “There were a lot of police outside screaming, ‘Get out of the house! Get of the house!'”

And everyone did make it out okay, but many were left struggling to understand why anyone would purposefully start a massive fire. Police said 21-year-old Brian Alejo is the alleged arsonist.

A Long Island man is accused of attacking his parents and then starting a fire Saturday in Cedarhurst. (Credit: Nassau County Police Department)

“I turned around, opened the window, and I saw flames coming from underneath the garage,” neighbor Leah Rosenberg said. “It’s very, very sad when you see something like that.”

Investigators told CBS2’s Roy that Alejo sneaked into the garage and hid for several hours before igniting the flames.

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But the rampage all began around the corner at his family’s home just after 1 a.m.

His mother, Rosa Alejo, was left with a black eye and told CBS2 in Spanish her own son punched her and then dragged her down the stairs after she tried to defend her husband. She said her son, who was likely on drugs, stabbed 51-year-old Victor Alejo 16 times for no apparent reason, sending him to the hospital for emergency surgery.

Police said Brian Alejo later turned himself in but then tried to run from officers, who had to restrain him. His mother said although he’s her son, he has to pay for what he did.

Brian Alejo is facing a slew of charges, including attempted murder and assault.

As for the families in the homes, they are currently staying in temporary housing.