President Donald Trump reacted to the news Wednesday that Mexican soldiers had detained and disarmed two members of the United States National Guard on American soil.

“Better not happen again!” Trump wrote on Twitter. We are now sending ARMED SOLDIERS to the Border.”

The American soldiers allowed themselves to be disarmed, according to reports, after the Mexican soldiers held them at gunpoint. They were released after the soldiers explained in Spanish that they were still on American soil.

“Though they were south of the border fence, US soldiers remained in US territory, north of the actual border,” CBP officials explained in a statement after the incident. “After a brief discussion between the soldiers from the two nations, the Mexican military members departed the area.”

Trump suggested that Mexico was detaining American troops as a “diversionary tactic” for drug smugglers acting on the border.

“Mexico is not doing nearly enough in apprehending & returning!” he wrote.

Trump also raised the alarm of an enormous caravan of migrants traveling up through Mexico.

“It has been reduced in size by Mexico but is still coming,” he wrote. “Mexico must apprehend the remainder or we will be forced to close that section of the Border & call up the Military. The Coyotes & Cartels have weapons!”

A very big Caravan of over 20,000 people started up through Mexico. It has been reduced in size by Mexico but is still coming. Mexico must apprehend the remainder or we will be forced to close that section of the Border & call up the Military. The Coyotes & Cartels have weapons! — Donald J. Trump (@realDonaldTrump) April 24, 2019