SAN FRANCISCO — Last month, the federal government issued a summons ordering Twitter to hand over information about an anonymous account that had posted messages critical of the Trump administration. Now, the government has blinked.

Customs and Border Protection on Friday withdrew its demand that Twitter unmask the anonymous account, a day after the social media company sued the government to block the summons. The person or people behind the account in question, @ALT_USCIS, had claimed to be a current employee of Citizenship and Immigration Services and had regularly posted messages at odds with White House policy.

The government’s move defused a potential standoff pitting a presidential administration that has tried to clamp down on leaks against a technology company with a history of defending its users’ First Amendment rights.

“Because the summons is now withdrawn, Twitter voluntary dismisses without prejudice all claims against Defendants in the above-captioned matter,” Twitter said in a filing of its own on Friday in which it withdrew its lawsuit.

The company declined to comment beyond the filing. Jenny Burke, a spokeswoman for the Homeland Security Department, which, with Customs and Border Protection, had issued the summons, did not immediately respond to request for comment

The case was spurred by a wave of so-called alt-accounts that emerged on Twitter after President Trump’s inauguration and he began cracking down on what federal agencies like the National Park Service could say on the social media platform, effectively blocking them from using it.

In response, anonymous Twitter accounts began to emerge offering “alternative” opinions at odds with the agencies’ official silence. Accounts like @Alt_Labor, @BadlandsNPS and @RogueEPAstaff claimed to be operated by current or former staff members at the agencies, dissident employees pushing back against what they considered the dangerous policies of the Trump administration.

@ALT_USCIS, created in January, has been active on Twitter in criticizing the administration’s immigration policies and other actions. On Friday, after news broke that the government had withdrawn the summons seeking information from Twitter, the account posted a message thanking those who had supported the right for anonymous free speech.