Midnight munchies were apparently to blame for a fire early Monday morning at a Butler apartment building.

The call about 12:35 a.m. for smoke coming from the building at 315 N. Washington St. triggered an initial evacuation of residents and for city firefighters to respond.

Officials soon tracked the smoke to one of the 24 apartments and tried to alert the tenant there, but to no avail.

The building owner eventually had to use a key to get inside.

That’s where authorities uncovered the source of the supposed fire — “a severely charred pizza” in the oven, according to a Butler police report.

The still snoozing tenant, 31-year-old Adam J. Aiken, was found unharmed. In plain view, police said, officials also found a marijuana pipe and other drug contraband.

While speaking to Aiken, the police report said, an officer noticed an empty stamp bag of suspected heroin “stuck to his left arm.”

The fire caused little if any damage and residents were soon allowed back inside, authorities said.

Fire crews were back at their station within an hour of the call.

Police on Monday charged Aiken with misdemeanor possession of drug paraphernalia.