The parents of intensive care nurse Alex Pretti said Tuesday the federal government is shielding the immigration enforcement officers involved in their son's killing, and no one from the government has reached out with any substantive information for nine months.

Michael and Susan Pretti called for the Department of Justice to hold accountable those who shot their 37-year-old son during President Donald Trump's ramp up in deportations targeting Minnesota.

Federal prosecutors disclosed in recent court filings they had stopped sharing evidence with Minnesota authorities who are investigating the January killings of Pretti and Renee Good by federal officers.