An iPhone seized from perpetrators of the December terrorist attack in San Bernardino, Calif., may contain evidence of a “dormant cyber pathogen” that poses a threat to residents of the county, the district attorney’s office claimed in a filing late Thursday.

“The seized iPhone may contain evidence that can only be found on the seized phone that it was used as a weapon to introduce a lying dormant cyber pathogen that endangers San Bernardino County’s infrastructure … and poses a continuing threat to the citizens of San Bernardino County,” the district attorney wrote.