The official White House Twitter account attacked two Democratic senators who have been critical of U.S. Immigration and Customs Enforcement (ICE).

Sen. Elizabeth Warren (D-Mass.), who recently called for abolishing ICE, and Sen. Kamala Harris (D-Calif.), who has been critical of the agency, both received direct tweets to their official Senate accounts.

“Why are you supporting the animals of MS-13?” a tweet at Harris on Monday read.

The White House Twitter account also linked to ICE press releases about recent deportations and the program overview for the Border Enforcement Security Task Force.

It’s common for President Donald Trump to attack his critics – by name or otherwise – on Twitter, but he uses his personal Twitter account (@realDonaldTrump). The official White House account (@WhiteHouse) has usually been used for less partisan messaging.

Calls for abolishing the agency have gained ground in recent weeks as the Trump Administration’s “zero tolerance” and family separation policies have created a political uproar.

Both senators are considered potential presidential contenders for the 2020 election, and Harris is a rising star in the Democratic party.

Harris replied to the White House tweets from her personal Twitter account, writing that she “went after gangs and transnational criminal organizations” as a prosecutor.

In May, President Donald Trump took heat for using the word “animals” to refer to MS-13 gang members.

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