The Missouri fire marshal's office is urging people to be cautious with fireworks, saying that people should light only one at a time and keep water nearby.
Sales of fireworks by licensed seasonal retailers in Missouri began last week and continue through July 9.
State Fire Marshal Randy Cole said the safest way to enjoy fireworks is to watch public displays by trained professionals.
Cole's office recommended that anyone drinking alcohol avoid handling fireworks and consider giving the duties to a "designated shooter."
The National Fire Protection Association said the U.S. has more fires on the Fourth of July than on any other day, more than half of them involving fireworks.
This announcement came after a 10-year-old St. Louis boy lost four fingers in a fireworks accident this weekend.
The St. Louis Post-Dispatch reported that Martinez Smith-Payne will have a second surgery on Monday. Police said he was hurt Friday night when he lit a firework while holding it in his left hand.
The boy's mother, Frances Smith, says her son was with his brother in a field near the family's house when they found the firework.
The boy is hospitalized in good condition at St. Louis Children's Hospital. Smith said her son is "in good spirits." Although he lost four fingers, he still has use of his thumb.
Police said the bomb and arson unit is investigating.