The FBI has sent out an alert to law enforcement in Colorado and Wyoming after chilling accounts of men described as "Middle Eastern" attempting to intimidate military families, Fox News has confirmed.

A senior government official said authorities are aware of reports of men approaching military families and questioning them about what their relatives in the service have been involved in, including one case in May in which the wife of a service member was told by two men her spouse was an “interrogator.”

"The woman had observed the vehicle in the neighborhood on previous occasions," the alert said.

The official said authorities are pursuing the accounts, but have no suspects.

CBS Denver obtained the alert and reported that "on numerous occasions" family members of military personnel were approached by these men who apparently wanted to obtain personal information about their spouses. 

The FBI's Denver bureau did not immediately respond to a Fox News inquiry. The Colorado Department of Homeland Security told the station it is aware of the situation, which has occurred throughout June 2015.

A Department of Defense official told Fox News that these types of incidents are reported from time to time and would not characterize the hostile questioners as part of a terror group. The official said military personnel and their family members should immediately contact local law enforcement should they observe or encounter suspicious or concerning activity.

The Pentagon has previously warned military personnel and their families of an ongoing threat to their safety, telling military families last year not to allude to their service in social media forums. 

“The FBI and DHS recommend that current and former members of the military review their online social media accounts for any information that might serve to attract the attention of ISIL [ISIS] and its supporters,” a federal bulletin sent to law enforcement agencies in November stated, advising that troops “routinely exercise operational security in their interactions online.”