When the smoke cleared early Tuesday, Westport firefighters and police found more than just old cars, tools and farm gear inside a ramshackle storage barn back in the woods off American Legion Highway (Route 177).

Fire crews and police officer Robert Rebello were working their way through one of the rental storage units at about 2:30 a.m. when they spotted guns — a rifle barrel and what appeared to be a gun with foldable stock — inside a car. They obtained a warrant and later found a small arsenal of  weapons and ammunition in the car.

They were still at it when, at about 5 a.m., a vehicle drove up and a man later identified as Roberto Rodriguez, 29, of 62 Ninth Street, Fall River walked up to investigators. When they learned that he was the one who had been renting the booth, they placed him under arrest.

Firefighters had responded to 212 American Legion Highway for a report of fire just after midnight. The found a large (100 by 500-foot) homemade storage facility with about 10 rental units located about a quarter mile off the road. Just under half of the structure was ablaze and it took about an hour to control the fire in frigid temperatures.

"None of the rental units had names or numbers on them but they were separated with plywood doors and locks," although some of the storage units were being used by a mechanic and had vehicles parked inside, said Detective Jeff Majewski.  Firefighters "gained entry into these plywood units to extinguish the fire and ensure that there was no extension of the fire as smoke had filled the building.

Police were called in as was the building inspector "as the structure had numerous building code issues including homemade heating units that were vented through plywood walls," Det. Majewski said. "That same structure had previously caught fire about one year ago.

The firearms found in the car included an AK 47-variant high capacity assault rifle with over 25 rounds of high-powered ammunition loaded into a magazine for that rifle.  A second rifle with a folded stock had a loaded 40 caliber magazine.  A third firearm resembled an Uzi assault gun which had a loaded 9mm magazine.

In addition to the firearms, investigators found hundreds of rounds of ammunition of various calibers inside a backpack.  There were also high capacity magazines for other firearms and over 10 grams of cocaine tucked in among the weapons.

Mr. Rodriguez was charged with three counts of possession of a large capacity firearm without a license, possession of large capacity feeding devices (gun magazines), possession of ammunition without a license, possession of a firearm in the commission of a felony (drug distribution), and possession with the intent to distribute  Class B cocaine.  The incident remains under investigation by police and town officials.