2:38 PM PT -- Hannah Gutierrez-Reed's attorney, Jason Bowles, tells us, "Something is rotten in Denmark. It is shocking that after 20 months of investigation, the special prosecutor now throws in a completely new charge against Ms. Gutierrez Reed, with no prior notice or any witness statements, lab reports, or evidence to support it."

He continues, "This comes on the heels of the state letting its lead investigator go, and the investigator raising serious concerns about the investigation in an email. This stinks to high heaven and is retaliatory and vindictive."

"Rust" armorer Hannah Gutierrez-Reed has found herself in the crosshairs of prosecutors once again, this time for allegedly transferring narcotics the day Halyna Hutchins was shot and killed on set.

According to legal docs, obtained by TMZ, Reed's been charged with tampering with evidence after prosecutors claim she, "did transfer narcotics to another person with the intent to prevent the apprehension, prosecution or conviction of herself."

The documents do not state what type of narcotic Gutierrez-Reed allegedly had in her possession, but the development is significant in light of other allegations prosecutors have made about the disgraced armorer.

In another filing last week, prosecutors accused Reed of drinking and using marijuana after working on the set ... explaining she may have shown up on the job hungover and lacking proper alertness and awareness to perform her duties efficiently.

At the time of the allegations, Hannah's attorney, Jason Bowles, told us, "The prosecution has so mishandled this case and the case is so weak that they are now resorting to character assassination tactics to further taint the jury pool. This investigation and prosecution has not been about seeking Justice; for them it’s been about finding a convenient scapegoat."

Hannah's also been charged with involuntary manslaughter for Hutchins' death.