PROVIDENCE, R.I. — A two-story wooden storage building where firefighters battled a four-alarm blaze Monday afternoon is a “total loss,” according to city officials. The fire, which also damaged the adjacent historic Carriage House, sent billowing smoke that could be seen from the highway.

“Losing the building is a shame, but nobody was injured and we’re thankful for that. That’s what is important,” said Mayor Jorge Elorza at a news conference in the park.

The fire began at about about 2:30 p.m., said Public Safety Commissioner Steven M. Paré. At this time, the fire does not appear suspicious, he said.

The storage building is located behind the Carriage House, which was converted to administrative offices.

There were one or two “early explosions” that likely came from “propane or fertilizer” stored inside the shed, Paré said. "There were chemicals in there — they were able to put that out pretty quickly."

“We’re not sure how it started,” Paré said. "It could have been accidental."

About four or five workers were inside the storage structure when the fire began, but they were able to get out. As ladder trucks poured water on the smoldering building, a dozen or more parks department employees watched from the parking lot up the hill. By 5 p.m., the smoke began tapering off.

The building held a substantial amount of the city’s smaller park equipment, like “wood, tools, mowers and play equipment,” said Park Manager Joseph G. Salem. It also included a carpenter's shop, and a stockroom.

Some 75 Providence firefighters responded, with six ladders; a dozen engines and three rescue trucks. Three cities provided mutual aid to cover Providence during the fire.

Paré said crews initially faced water challenges because of the park’s loop system. "When they drew from the hydrants, the water pressure began to drop," he said. Firefighters were able to pull water from a nearby pond to douse the flames.

Elorza said the city is insured against the loss, and his legal team is working with insurance agents.

Elorza said the city will temporarily relocate offices and workers, but park service will not be disrupted. He praised the firefighters and other responders, noting, "We have a great team."