The US Court of Appeals for the Fifth Circuit ruled Tuesday that President Donald Trump’s administration cannot invoke the 1798 Alien Enemies Act (AEA) to deport Venezuelan nationals and enjoined Trump from deporting two Venezuelans under the AEA.

According to the court, the AEA is “applicable only in the event of a declared war, an invasion, or a predatory incursion by a foreign nation or government, and it allows the President to detain alien enemies.” In 1952, the US Supreme Court ruled that when Congress terminates a war, the president’s power to invoke the act ends. However, the Fifth Circuit noted, “The other possible foundational events for invoking the AEA, an invasion or a predatory incursion, are for the President to determine.”

The president issued a presidential proclamation on March 14 alleging that the Venezuelan gang “Tren de Aragua (TdA) operates in conjunction with Cártel de los Soles, the Nicolas Maduro regime-sponsored, narco-terrorism enterprise based in Venezuela, and commits brutal crimes, including murders, kidnappings, extortions, and human, drug, and weapons trafficking.” The proclamation claimed that the group was engaged in a predatory incursion under the AEA.

The court decided that:

[A] “predatory incursion,” as used in the AEA, definitely applies to an unauthorized entrance by units of another nation’s military to commit acts that are destructive to the interests of the United States, such as victimizing its people or property, for the benefit of a foreign power or its agents without the necessary objective of a long-term occupation or control of American territory.

In March, the US District Court for the District of Columbia found probable cause for holding the Trump administration in contempt after they refused to halt the removal of Venezuelan nationals being deported under the AEA while they were in flight. In May, rights groups urged the US to repeal the Alien Enemies Act because obligations under international law have changed since the act was enacted.