Fire Captain John Kemper, who was injured fighting a fire on July 5, died Wednesday.

According to a press release from St. Louis Fire Department, Kemper was one of four firefighters injured during the overnight hours from July 4 to July 5. He was injured fighting a fire on the 3600 block of Pennsylvania Avenue.

Garon Mosby, a spokesman for the St. Louis Fire Department, said Kemper was hospitalized with a shoulder injury, but other issues were found and he was moved to the ICU. He was released from the hospital and was out of town relaxing with his family when he died Wednesday morning. Mosby said the department does not know an exact cause of death.

Kemper joined the St. Louis Fire Department in 1993 and was promoted to captain in 2008.

Mosby said the department does not know the cause of the fire on Pennsylvania, but St. Louis Fire Chief Dennis Jenkerson said in an interview last week that they responded to hundreds of fireworks-related fires in a 24-hour period ending on July 5.

“70-plus dumpster fires, 30-plus weed or grass fires, 10 garage fires. We also had a total of 13 building fires,” said Jenkerson.

An investigation into the cause of the fire on Pennsylvania was not initially planned because it would be too dangerous for investigators. Mosby said the neighbors complained that a large number of fireworks were set off.

For years Jenkerson has heard fireworks fans say it’s tradition to shoot fireworks, even when it’s considered illegal. Jenkerson said there’s no level of being careful with fireworks.

St. Louis police said there were no fireworks-related summons issued July 4.

Two of the firefighters injured during the same shift have returned to full duty and one has returned to light duty.

Backstoppers says it is aiding Kemper's family.