SANTO DOMINGO, Dominican Republic (AP) — Firefighters struggling to extinguish a blaze caused by a deadly explosion near the Dominican Republic’s capital this week found two more bodies Wednesday, bringing the death toll to 13, authorities said.

The number of victims is expected to increase since responders have not been able to fully access the building where the explosion occurred Monday at a bakery in the city of San Cristobal, which lies just west of the capital of Santo Domingo.

An additional 10 people remain missing, with anguished friends and family pacing outside hospitals and morgues in anger and frustration, saying no one has been providing them information.

Jaissy Capellán, press coordinator for the Emergency Operations Center, told The Associated Press that the two additional bodies were pulled from the rubble early Wednesday.

Meanwhile, authorities are probing what might have caused the explosion, vowing to crack down on any business that might not have been following regulations.

Juan Manuel Méndez, director of the Emergency Operations Center, said at a news conference late Wednesday that if an unidentified factory was operating illegally as some residents have alleged, the investigation would shed light on that.

“If there is some type of culpability or not, the investigation will determine that,” he said. “We will take legal action.”

At least 59 people were injured in the blast, which occurred in a bustling commercial area in the city’s center and destroyed four buildings and damaged nine others. More than 30 people remain hospitalised with conditions including fractures, burns and respiratory problems. Two firefighters also were treated for smoke inhalation.

More than 30 ambulances and some 500 personnel including rescuers and officials responded to the incident.

Toxic smoke still hovered over the explosion site, with health officials urging people to wear face masks.

San Cristobal, the birthplace of dictator Rafael Trujillo, was the site of another explosion nearly 23 years ago. An arms depot exploded in October 2000, killing at least two people and injured more than two dozen others, forcing authorities to evacuate thousands.