Updated

The theft of explosives from a Missouri firing range has officials worried terrorism may be involved, according to a report in the St. Louis Post-Dispatch.

Authorities discovered the theft Tuesday and said an unknown quantity of dynamite, C-4 and other explosives were stolen sometime during the last 10 days.

Officials believe more than one person may have been involved in the theft, but it is too early to know their intent, including whether terrorism could be involved, the paper said.

"These items are all extremely dangerous," said Mike Schmitz of the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

Click here to read the St. Louis Post-Dispatch report.

The items were taken from a federally approved storage magazine, which looks like a large construction dumpster, Schmitz told the Post-Dispatch.

The St. Louis County firing range is used by the sheriff's office and the FBI, the paper reported.

"Anytime any explosives are in the hands of the wrong people, we're concerned about it, and we're working closely with all area law enforcement to try and locate the stuff," FBI Assistant Special Agent in Charge Tom Noble told the paper. "Obviously, we take this very seriously."

The FBI is offering a reward. Anyone with information was being asked to call 314-231-4324.

Click here for FOXNews.com's Crime center.