(AP) U.S. attorneys announced indictments Friday against four additional central Missouri businesses and nine people accused of selling synthetic marijuana in what some defense attorneys described as a relatively new use of federal prosecutorial powers.
The indictments take aim at products that often are marketed as incense but that prosecutors contend are intended to be used as a marijuana equivalent. Although the mixtures are not specifically banned, prosecutors are citing a federal law that allows charges for products containing chemicals that are similar to controlled substances.

Two Columbia businessmen pleaded not guilty Thursday to a similar indictment alleging a $2 million conspiracy to sell synthetic marijuana. A Springfield woman pleaded guilty to a similar $1.3 million synthetic marijuana case in July.
Federal prosecutors also have been pursing synthetic marijuana cases in other parts of the U.S., most notably winning the conviction of a Minnesota man last week on 51 of the 55 charges he faced.
The products often include plant materials that have been sprayed or mixed with chemical compounds that are difficult for authorities to regulate because of the constantly changing formulas used in the mixtures.

The Missouri indictments announced Friday actually were handed down earlier this month under seal, but a spokesman for the U.S. attorney’s office said they weren’t previously disclosed because of the partial federal government shutdown.
Some defense attorneys have questioned whether federal authorities should be targeting businesses for selling products not explicitly banned by federal law.
“My client had every product that he brought into his store tested by an independent laboratory, and it was always found to be negative of any of the chemical formations that have been designated as not being legal,” said Bret Rich, an attorney for defendant Charles Austin Jr. and the Puff N Snuff stores that Austin operates in Eldon and Camdenton.
“He’s tried to do everything he can to try to stay within the law,” Rich said.
Austin, 61, of St. Charles, has pleaded not guilty to the federal charges.
Others named in the indictment include the Columbia businesses Dynamic Scents and Order Refill; Mozark Products in Jefferson City; siblings Mathew Hawkins, 38, Patrick Hawkins, 31, and Molly Carmichael, 36, all of Columbia; Alexander McMillin, 29, of Columbia; Kent Holtz, 42, of Kaiser; Chadwick Schlicht, 43, of Osage Beach; Scott Hanson, 47, of Versailles; and Thomas McCormack, 28, of Jefferson City.
The three siblings are the children of John Hawkins, 51, of Columbia, whose separate indictment with Kevin Bay on synthetic marijuana charges was publicly released Thursday by U.S. attorneys. Bay and Hawkins operate the Bocomo Bay retail store in Columbia and have both pleaded not guilty.
McMillin, Hawkins and his family are represented by Columbia attorney Dan Viets, who had said Thursday that he plans to challenge federal assertions that the products are illegal.
An attorney for Schlicht said his client pleaded not guilty during a court appearance Friday.
Attorneys for the other defendants did not immediately return telephone messages Friday.