Twitter’s free speech battle with the U.S. Department of Homeland Security ended quickly: The social media company today withdrew the suit it filed yesterday charging that the government sought to “unmask” an anonymous user who had been critical of the administration.

The Justice Department just told Twitter that DHS’ Customs and Border Protection unit “has withdrawn the summons” sent last month seeking the user’s name, the company says today in a filing at the U.S. District Court for northern California.

“Because the summons has now been withdrawn, Twitter voluntary dismisses without prejudice all claims against Defendants,” Twitter told the court.

Yesterday’s suit said that on March 14 the government sent Twitter an administrative summons demanding it provide “records that would unmask, or likely lead to unmasking, the identity of the person(s)” behind an account named @ALT_USCIS that criticized DHS’ Citizenship and Immigration Services unit.

This is one of several accounts created by people who claim to be current or former employees of federal agencies and “provide views and commentary that is often vigorously opposed, resistant, or ‘alternative’ to the official actions and policies of the new Administration,” the suit said.

Other accounts with similar @ALT titles are critical of the Labor Department and the Bureau of Land Management.

Disclosure of the anonymous tweeters “would have a grave chilling effect on the speech of that account in particular and on the many other ‘alternative agency’ accounts that have been created to voice dissent to government policies,” Twitter said.

When Twitter contacted a Customs and Border Protection agent who sent the summons, the suit says he “stated vaguely that he is conducting an investigation. But he did not identify any law or laws that he believed had been broken or point to any evidence substantiating any such belief—such as particular Tweets that he believes were unlawful.”