Looks like we got a real badass here!
ICE/HSI is the investigative arm of Homeland Security charged with crimes involving immigration, customs, sex trafficking, child pornography, intellectual property theft, trading in sensitive technology, money laundering, identity fraud, passport fraud, financial fraud, arms trafficking, terrorism, drug smuggling, and national security.
You don't have to be an alien for ICE/HSI to arrest you for any crime against the United States.
The statutory authority of ICE agents and officers now falls under two Titles of the US Code after the merger of INS and Customs into one investigation agency now known as ICE and also Homeland Security Investigations (HSI).
8 U.S. Code § 1357 - Powers of immigration officers
(5) to make arrests—
(A) for any offense against the United States, if the offense is committed in the officer’s or employee’s presence, or
(B) for any felony cognizable under the laws of the United States, if the officer or employee has reasonable grounds to believe that the person to be arrested has committed or is committing such a felony
Under regulations prescribed by the Attorney General, an officer or employee of the Service may carry a firearm and may execute and serve any order, warrant, subpoena, summons, or other process issued under the authority of the United States.
19 U.S. Code § 1589a - Enforcement authority of customs officers
Subject to the direction of the Secretary of the Treasury, an officer of the customs may—
(1) carry a firearm;
(2) execute and serve any order, warrant, subpena, summons, or other process issued under the authority of the United States;
(3) make an arrest without a warrant for any offense against the United States committed in the officer’s presence or for a felony, cognizable under the laws of the United States committed outside the officer’s presence if the officer has reasonable grounds to believe that the person to be arrested has committed or is committing a felony; and
(4) perform any other law enforcement duty that the Secretary of the Treasury may designate.
Are they police?
POLICE - the civil force of a national or local government, responsible for the prevention and detection of crime and the maintenance of public order.
Hell, they look pretty policey to me...