MIAMI -

A fire swept through a strip mall in Miami Wednesday night, killing 30 puppies in a pet store, say fire officials.

Firefighters responded to the two-alarm blaze at Northwest 7th Avenue and 37th Street about 10 p.m. after several 911 calls of heavy smoke billowing from a building.

An electrical overload at Fancy Beads caused the fire, investigators say.

"Whatever it's like, it's been like that for 10 years, so I have no idea what happened," said John Martinez with Fancy Beads. "It looks like it started right here because it went over that way."

The flames quickly spread to a neighboring bakery, restaurant, a pharmacy, and Beverly Hills Puppies. The mall is located just northeast of the Magic City Casino, formerly known as the Flagler Dog Track.

"They normally retail for about $2,000, $2,500 a piece and we lost 30 of those," said Martin Leon with Beverly Hills Puppies. "The fire department attempted to come in through here but because there's steel bars, it took them longer than normal, and by the time they entered the facility, the puppies had passed away because of the smoke, not as a result of the fire."

Each English and French bulldog puppy was inside a cage when the fire started. Some of the 8 to 9-week-old dogs had been sold and were awaiting for their new owners to arrive.

"We had to put them in bags this morning so the sanitation department of Miami-Dade could take them, and that really hits you," said Leon.

Other neighboring businesses also suffered heavy damage.

"We have no power. We have no gas. We have no water -- nothing," said Alejandro Medina with Cantina La America.

Medina added the restaurant serves 450 senior citizens each day.

The county deemed several of the businesses unsafe structures. Only a few of the owners had insurance.