"If these sanctuary cities are going to harbor and conceal criminal illegal aliens from ICE, which is in direct violation of Title 8 of the U.S. Code, federal arrest warrants should be issued for their elected officials," Hodgson said. "Our citizens would be safer if we never stopped enforcing immigration law and if we never formed or turned a blind eye toward sanctuary cities."

He also took aim at a Massachusetts legislator who passed along rumors of a planned ICE raid in Brockton on Tuesday and Wednesday.

Rep. Michelle DuBois, D-Brockton, warned her constituents in a Facebook post "if you are undocumented don't go out on the street. If there is a knock on the door of your house and you don't know who it is, don't open the door."

Hodgson called her actions "outrageous."

"This is the most outrageous, outrageous example of what is going on across the United States that is undermining my job and every other law enforcement officer in the United States," he said.

"I think you know that the Metropolitan Police Department does not ask questions about immigration status," he said.

"It's a long-standing policy of the Metropolitan Police Department not to enforce civil immigration law," Newsham continued. "We believe that the enforcement of civil immigration laws creates a divide between us and the community we serve and at the end of the day we believe that will make our community less safe. As the Chief of Police, I don't think I should be involved in any behavior that makes our city less safe."

Newsham said that in a discussion with the U.S. Attorney General, major city police chiefs collectively expressed their view that civil immigration enforcement is not the role of major police departments.

"The District - we are not responsible for civil immigration enforcement, like the Chief said," Bowser stated. "Our job is to enforce the laws of the District of Columbia and we are not local I.C.E. officials."

"We are not; however, a harbor for criminals - no matter where you're from," she added. "The police department will deal with criminals - violators of the law. They will be charged, they will be prosecuted, and they will be held."

"I don't think our policies are in violation," Bowser said. "The Federal Government does not compel the District to do its job. And the Federal Government's job is immigration enforcement."

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In a letter handed to the President of the EU Council Donald Tusk by the UK's ambassador to the EU Tim Barron, May stressed the UK's primary intent is to maintain a "deep and special partnership" EU members.

However, the letter's positive vibes soon took a more threatening tone.

"In security terms, a failure to reach agreement would mean our cooperation in the fight against crime and terrorism would be weakened," the PM said.

The European Parliament's Brexit negotiator Guy Verhofstadt told MEPs it is unacceptable for the UK to use its strength in intelligence and security services as leverage to secure a good trade deal from EU negotiations.

When asked if he thought May's suggestion amounted to blackmail, Verhofstadt said: "I tried to be a gentleman towards a lady, so I didn't even use or think about the use of the word blackmail.

"I think the security of our citizens is far too important to start a trade-off of one and the other," he said.

"Both are absolutely necessary in the future partnership without bargaining this one against the other."

May shrugged off accusations in the House Commons of using security cooperation as a "bargaining chip" to obtain a good deal for the UK.

"We will not be trading the security of our country, but we have a relationship with the EU," she said.