BOSTON (AP) — Four former employees and an owner of the Massachusetts facility responsible for a nationwide fungal meningitis outbreak that killed 76 people and sickened hundreds were convicted Thursday on charges including mail fraud and conspiracy to defraud the United States.

A Boston jury acquitted another employee, pharmacist Joseph Evanosky, of all charges after several days of deliberations.

The defendants were among 14 people charged in 2014 following an investigation into the outbreak, which sickened almost 800 people and is considered the worst public health crisis in recent U.S. history. The outbreak was blamed on contaminated injections of medical steroids made at the now-closed New England Compounding Center in Framingham, given mostly to people with back pain.

Prosecutors said the New England Compounding Center made drugs in unsanitary conditions, sent untested products and deceived regulators. The workers convicted Thursday were not accused of producing or sending the injections that caused the outbreak but of sending and approving other contaminated and substandard drugs.

Another pharmacist, who ran the so-called clean rooms where the tainted drugs were made, and another owner of the facility are already serving prison sentences for their roles in the outbreak.

A lawyer for Evanosky said he's grateful for the jury's verdict.

"He was an innocent man who never should have been charged in the first place," Mark Pearlstein said.

Among those found guilty was part-owner Gregory Conigliaro, who was charged with conspiring to defraud the Food and Drug Administration. His lawyer declined to comment.

Pharmacist Gene Svirskiy was the only defendant convicted on the most serious charge of racketeering and was also found guilty on conspiracy and mail fraud charges. An email requesting comment was sent to a lawyer for Svirskiy.

An attorney for another defendant, pharmacist Christopher Leary, said he was pleased that Leary was cleared of the most serious charges but was disappointed that jurors found him guilty of other counts. Lawyer Paul V. Kelly said the legal team plans to file post-trial motions and will appeal if necessary.

Other defendants were cleared of some charges and convicted of others.

In January, Glenn Chin, a supervisory pharmacist, was sentenced to eight years in prison after he was convicted of racketeering and mail fraud. He was cleared of second-degree murder charges, which could have brought a life sentence.

Read more: Pharmacist Charged In Meningitis Outbreak Sentenced To 8 Years In Prison

Co-Owner Barry Cadden is serving a nine-year prison term for his role in the outbreak. He was also acquitted of second-degree murder.