San Juan.– Authorities in Puerto Rico on Friday ordered the evacuation of hundreds more residents from homes around a huge fire at an oil depot which spewed a column of toxic black smoke into the sky near the capital San Juan.

Some 130 firefighters, backed by National Guard troops, were still trying to put out the massive fire, hours after an early morning explosion triggered the blaze at the Caribbean Petroleum Corp. storage facility at Bayamon.

After initially destroying 11 tanks at the 40-tank site, the fire spread to at least six more, containing products such as jet fuel, bunker fuel and gasoline. It was one of the largest fires ever in the U.S. Caribbean island territory.

"There are 17 tanks ablaze, and the firefighters are cooling the rest to avoid their explosion," Puerto Rico Governor Luis Fortuno said. He declared a state of emergency in San Juan and four surrounding towns.

As flames licked up to a height of 100 feet over the oil facility, pushing a mushrooming black plume of smoke into the air, Fortuno announced the mandatory evacuation of the Sabana Amelia neighborhood, where around 1,000 to 1,500 people lived. The neighborhood is in the same Catano district from where around 350 people were evacuated earlier.