VAIL, Colo. — An immigrant rights group said several Ace of Spades cards with an address pointing to an immigration detention center were found inside vehicles of people who were detained by ICE enforcement last week.

Alex Sanchez of Voces Unidas said about nine people were detained and at least two of the “death cards” were found in their vehicles by their families.

The cards contain the words “ICE Denver Field Office” and an address that points to an immigration detention facility in Aurora. The cards are reminiscent of the “death cards” used by US soldiers who would place an Ace of Spades on the bodies of Viet Cong soldiers during the Vietnam War.

In a statement sent to The Denver Gazette’s news partners 9NEWS by a Department of Homeland Security spokesperson, the agency condemned the cards.

“ICE is investigating this situation but unequivocally condemns this type of action and/or officer conduct. Once notified, ICE supervisors acted swiftly to address the issue.

For more on this story, visit our news partners at 9NEWS.com.