Twitter filed a suit against the US Department of Homeland Security (DHS) on Thursday (6 April) to try to keep private the identity of an anti-Trump account, as the DHS made attempts to unmask the person behind it.

The suit, filed in the US District Court in Northern California, says the DHS attempted to demand Twitter give up information that would identify the person behind the account @ALT_USCIS. It argues this would go against the anonymous user's first amendment rights: the right to free speech.

More from IBTimes UK

The @ALT-USCIS account is part of a number of "alternative" government agency accounts that sprung up in the wake of Donald Trump's inauguration to protest against the government - purportedly from people working inside those agencies.

This particular account is an alternative to the United States Citizenship and Immigration Services, an agency within the DHS.

"On March 14, 2017, [DHS] issued and delivered to Twitter an administrative summons ... demanding that Twitter provide them records that would unmask, or likely lead to unmasking, the identity of the person(s) responsible for the @ALT_USCIS account," the suit read.

Some have noted that the suit consistently uses the word 'unmask' or variants of it, in a possibly veiled knock at the administration's recent anger at the alleged 'unmasking' of Trump campaign officials in intelligence by Obama administration officials.

The lawsuit said that the only authority DHS has to issue such summons is for "a narrow class of records relating to the importation of merchandise," adding that the summons "plainly has nothing whatsoever to do with the importation of merchandise into the United States".

IBTimes UK reached out to the US Department of Homeland Security for comment but was told they do not comment on pending litigation as a matter of policy. When contacted, Twitter said that there was no further statement than the original filing.

However, the filing of the suit seems to have emboldened the people behind the account, which now boasts the US Constitution's First Amendment as its pinned tweet.

The American Civil Liberties Union also voiced support for the suit, saying they were "glad Twitter is pushing back. We'll be going to court to defend this user's right to anonymous speech."

Twitter