The morning was quiet at the Roszke/Horgos crossing, but the action began at around 3 p.m. local time, when the police presence was increased from normal patrols to include police cars speeding near the border crossing with a few ambulances in tow, according to an ABC News reporter at the scene.
A water cannon has also been activated and a police helicopter is hovering over the scene.
The special TEK Hungarian paramilitary troops followed. The troops are outfitted with sidearms, helmets, face masks, all in black uniforms.
Once situated, the troops moved in formation towards the Serbian side of the border.
There are about 300 special Hungarian TEK paramilitary officials in the area near the Serbian border town of Horgos.
Young men who appeared to be refugees were seen running in spurts away from the border, wiping their eyes, and some were seen pouring bottles of water on their eyes, as seen on a live video feed from the Serbian side of the border.
The escalation comes as tensions reached a new high, with several European countries -- including Hungary -- enacting new restrictions barring most refugees entry.
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