Monday's fire outside an apartment in Charleston's college district has several similarities to the string of 80 suspected arson cases that have plagued the peninsula for a decade.

But perhaps most concerning this time is that somebody would have had to pass through two swinging gates to reach where two fires may have been intentionally set.

"There was no reason for two fires to be there," said David Fromholz, who with his wife, Barbara, were awakened at 3:30 a.m. to the smell of smoke inside.

City fire officials are investigating the fire at 50 Montagu St. near Ashley

Avenue as "suspicious" but are not ready to confirm if there's a link to the string of serial arsons that have struck dozens of residences and apartments downtown since the early 2000s.

Charleston Fire Department spokesman Mark Ruppel said it will be several days before a connection might be determined. Evidence taken from the scene is now in the hands of the State Law Enforcement Division.

Top among the similarities to the serial arson file are its early morning reporting time, and an origin-point near a porch and apartment entrance.

Another oddity in the case is that the Montagu Street fire is "definitely out of the target area," Ruppel said, of the arsonist's suspected strike zone around the Charleston Crosstown.

Ruppel also confirmed that a fire last month at 61 Amherst St. that gutted a two-story house on Charleston's East Side is not connected to the arson wave.

Fromholz said Monday's fire appears to have started in two places: near a ground-level air-conditioning unit, and also several feet away and higher up a set of wooden stairs. To reach either point, someone would have had to cross through two unlocked gates, he said.

A bicycle stored near the air conditioner was partially burned, he added, causing a tire to melt and permeate the area with a rubbery smell. Otherwise, damage was mostly limited to a staircase, the air-conditioning unit and to an outside wall, though a smoky smell lingered inside the Fromholz apartment.

Prior to Monday's report, at least 83 suspicious fires have been set downtown since 2002, many with the common thread of beginning on a darkened porch and early in the morning. Fear of another arson attack probably played a role in the city's large response, the Fromholzes said, with at least 12 emergency response vehicles lining the streets in minutes.

"You say you've got a porch fire," David Fromholz said, "and they respond really quick."

The Fromholzes said the takeaway from the incident should be that everyone living downtown immediately check their smoke detector batteries to make sure the devices work.

"We had four or five (alarms) in the house and that's what saved us," David Fromholz said.

Reach Schuyler Kropf at 937-5551.