Long Beach police arrested a man on suspicion of attempted murder after he lit the inside of his neighbor’s apartment on fire Saturday, according to authorities.

Investigators aren’t sure yet what drove him to start the blaze, which charred some curtains and interior walls, Long Beach Fire Department Capt. Matt Dobberpuhl said.

The 52-year-old is accused of sparking the flames around 8:15 a.m. Saturday at an apartment near 10th Street and Roswell Avenue, a few blocks from Wilson High School.

Fire officials only needed to send one engine to the blaze, which was already out by the time they arrived, Dobberpuhl said.

Neither of the men who live in the apartment were hurt, he said. Investigators estimated it did about $500 in damage.

Police, however, booked the man, identified as Ryan Richardson, on suspicion of attempted murder and arson.

Jail records show he lives in the same apartment building where he allegedly sparked the flames.

He was being in lieu of $1 million after police arrested him miles away from his home Sunday afternoon, jail records show.