Movement Ink, a screen printer based in California, is suing the U.S. Postal Service for allegedly seizing shipments of Black Lives Matter masks, NBC News reports. The masks, which had slogans like “Stop killing Black people” and “Defund police,” were bought by the Movement for Black Lives (M4BL) and were intended to be shipped to Washington, D.C., St. Louis, New York City and Minneapolis following George Floyd’s death in 2020.

Four boxes, each containing roughly 500 masks, were marked “seized by law enforcement” while they were en route to their destinations, HuffPost reports, and shipments were delayed by more than 24 hours.

According to NBC News, the lawsuit was filed on Wednesday by Institute for Justice, a libertarian-leaning nonprofit law firm. It argues that USPS and U.S. Postal Inspection Service officials violated constitutional rights under the Fourth Amendment by improperly seizing the boxes without probable cause, a warrant or reasonable suspicion. The lawsuit also suggests that the officials’ questionable conduct was because of the masks’ messaging.

A letter regarding the incident that was sent from the Postal Service to Rep. Barbara Lee in June 2020 alleged the parcels “were detained solely because the external physical characteristics of the parcels were consistent with parcels in other non-related instances that were confirmed to contain nonmailable matter, specifically controlled substances.”

However, the lawsuit states it’s “not clear” whether the defendants knew what was in the boxes. But they did have “neatly taped, nondescript brown boxes” with clear labels, noting that they were “BLM MASKS,” though it has not been confirmed when that note was added.

Movement Ink owner René Quiñonez shared with NBC News that the business has been negatively impacted by the seizure.

“For us as an organization, as a company, and as part of our community, our intent was to support the many activities that were going on across the country,” he said, according to NBC News.

According to the lawsuit, the masks “created a pall of suspicion, distraction, uncertainty, and confusion around René and Movement Ink.” It also deems the searches “baseless,” and states that it caused emotional and mental distress “not just because of his and Movement Ink’s financial and reputational hits, but because he and Movement Ink have been effectively shut out of a movement and a community that they spent (and continue to spend) years investing their time and energy in.”

Quiñonez is hoping that this opens up conversations about searches and seizures and what motivates them.

“The fact that our government can just seize private property — either because of just general suspicion or because they know its political commentary — that’s a scary reality that we live in,” he said.