A Fed Ex driver was knocked unconscious after breathing in fumes from one of the packages he was delivering Tuesday.

36-year-old Chris Watson collapsed inside his truck at the loading dock of Ocala Regional Medical Center. Marion County Fire Rescue responded to the scene after a passerby noticed Watson.

Fire rescue workers said the driver had smelled a sweet odor coming from one of the packages, and was knocked unconscious. Watson was treated by EMTs, and a hazardous materials team was called in to investigate the package.

"We were pretty much able to determine that it came from an area where they had some packages for some fuel additives and cleaners, and we feel that it was probably a package that leaked in that area," Ocala Fire Rescue Cpt. Larry Doerffel said.

In the last two days, there have been more than 20 suspicious letters containing white powder that have been delivered to various addresses. The Ocala Police Department said Tuesday's incident is not related to these letters.