Most of the 3.5 million residents of Puerto Rico have spent two days without power as the result of a fire at Aguirre power plant in the southern town of Salinas, according to the Associated Press.

Executive director Javier Quintana said initial investigations suggest that lightning caused one transmission line to fail which in turn caused a switch to explode and catch fire. The Electric Power Authority said the fire knocked out two 230,000-volt transmission lines connected to the larger power grid, which tripped circuit breakers, automatically cutting off electricity.

Gov. Alejandro García Padilla acknowledged “…the [power] company's maintenance problems began decades ago." With $9 billion in debt and several corruption allegations, the electric company has struggled to update outdated infrastructure and equipment. However, García Padilla insisted that these maintenance issues were not related to the fire.

The blackout began early Wednesday afternoon, leaving almost all of Puerto Rico without electricity and roughly 205,000 individuals without water. In addition, electrical malfunctions caused 15 fires across the island. In response, Gov. García Padilla declared a state of emergency and activated the National Guard.

To complicate matters further, heavy storms on Thursday caused areas where electricity had been restored to lose power again. 

During the outages, residents had no air conditioning in the intense island heat. People moved their mattresses onto porches or balconies to sleep. Others took refuge in their cars and a few were able to snag hotel rooms before they were quickly gobbled up.

Without electricity, police officers were needed to direct traffic and public schools were closed Thursday and Friday.

Despite the turmoil, very few injuries were reported. A 76-year-old man went to the hospital in good condition after spending the night trapped in an elevator. Also, four police officers were hit by cars while directing traffic, but all are expected to recover. The only death reported was caused by carbon monoxide exposure from a personal generator.

By Friday morning roughly 75 percent of the 1.5 million home and businesses had electricity. Authorities believe most Puerto Ricans will have power by Saturday.