Zachary Frost, age 28, of 1632 New Boston Road, Francestown

NASHUA – Francestown resident Zachary Frost, whose criminal history includes numerous arrests mainly on drug-related offenses and a couple of brief stints in jail, is now under indictment on several charges accusing him of threatening to harm a witness against him.

Frost, who turned 28 last month, allegedly sent threatening letters to the woman “with the purpose to terrorize” her by various means, according to the indictments, which are among those handed up in May by a grand jury for Hillsborough County Superior Court South.

Frost allegedly addressed the letters to the alleged victim and sent them to a Nashua physical therapy practice, where she had previously worked, according to the indictments and police reports.

The charges on which the grand jury indicted Frost include one count of witness tampering – induce another, a Class B felony that accuses Frost of intimidating the woman by sending a letter “containing specific threats to her safety in retaliation for contacting” Nashua police.

The other four indictments are on the charge of criminal threatening, all of which are Class A misdemeanors.

They accuse Frost of stating in the letters to the woman that “her car would be run off the road, causing an accident; that he had an AR-15 (rifle) with her name on it; that he would use Nitroglycerin, blasting caps, and black powder to commit arson on her former office building; and that he would burn down her former office building,” the indictments state.

Two of the letters were sent March 2, one on March 3, and the two others on March 24.

Nashua detectives investigating the alleged threats said at the time that the letters had been sent from the Hillsborough County Department of Corrections – Valley Street jail in Manchester – where Frost was incarcerated at the time.

The detectives eventually issued a warrant and charged Frost with the offenses.

According to court records, Frost has a history of arrests, mainly on drug-related allegations, that span three judicial jurisdictions: Hillsborough South, Hillsborough North, Cheshire and Merrimack counties.

One of those arrests, in October 2016, involved nine charges: Five counts of “presenting self as a pharmacist etc,” three counts of violating the controlled drug act and one count of obtaining drugs by fraud or deceit, according to his case summary.

About four months later, in early 2017, the record shows that all the counts were dismissed without prejudice.

The summaries also show that Frost reached plea agreements with prosecutors in two other cases. He was given a suspended sentence in one of them, and appears to have served roughly 6 months of a 12-month jail sentence after agreeing to plead guilty to drug-related offenses last September.

Frost’s Cheshire County case, which stems from his arrest in Jaffrey on a drug-related offense, is scheduled for a plea and sentencing hearing on July 14, according to the case summary.

Dean Shalhoup may be reached at 594-1256 or dshalhoup@nashuatelegraph.com.