A federal grand jury has indicted a 59-year-old man for illegally applying pesticides that left a Wilmington family  vacationing in a condominium in the Virgin Islands gravely ill in 2015, the U.S. Department of Justice said Friday.

Jose Rivera, who worked for Terminix International and was a branch manager for the company in St. Croix, knowingly sprayed fumigants containing the odorless chemical methyl bromide to exterminate pests inside residential units in several locations on the Virgin Islands, the Justice Department statement said. Indoor use of the pesticide was banned in 1984 because of its nerve toxicity.

In March 2015, the Esmond family checked into a condo on St. John that was directly above a unit that had been sprayed. Stephen Esmond became paralyzed and his teenage sons were in critical condition when they were airlifted to Philadelphia hospitals for treatment. Only their mother, dentist Theresa Devine, was able to be discharged from the hospital soon after the exposure.

Earlier this year, Terminix was sentenced to pay $9.2 million in criminal fines and restitution. The company was also ordered to perform community service to train commercial pesticide applicators, the Justice Department said.

Last year, the corporate parent of Terminix reached a tentative agreement to pay $87 million to the Esmond family.

In September 2015, the family met Pope Francis during his visit to Philadelphia. At the time, Esmond, an administrator at the Tatnall School in Wilmington, still suffered tremors and struggled to speak, family attorney James J. Maron told CNN. The family has declined media interviews.