DHS chief defends federal agents in Portland: "We will not retreat"

"We will not retreat. We will continue to take the appropriate action to protect our facilities and our law enforcement officers."

Driving the news: Reports that federal law enforcement officers in unmarked vehicles detained Portland protesters without explanation has attracted widespread criticism from leading Democrats, who've demanded a probe. Sen. Rand Paul (R-Ky.) on Monday added his voice to those denouncing the use of federal agents against protesters.

• The U.S. Attorney for the District of Oregon has called for an inspector general investigation into the reports.
• But Wolf dismissed the criticism, saying: "The smear attacks leveled against our officers is disgusting."

What to watch: The Oregon's attorney general's office has opened a criminal investigation into an incident resulting in the injury of a protester.

• The state attorney general filed a lawsuit in Federal District Court seeking a restraining order, accusing federal agents of unlawful tactics.

The big picture: Black Lives Matter protests swelled in Portland this week despite the presence of federal law enforcement officers. Demonstrations against police violence have continued in the city for more than 50 days, Axios' Orion Rummler notes.

Go deeper: In photos: Unrest at Portland protests amid federal force presence