Venezuela has extended a partial border shutdown with Colombia and sent another 3,000 troops to the area in a crime crackdown.
Mr Maduro has shut a crossing in the state of Zulia and declared an emergency in three of its cities.
He says the border area has been infiltrated by Colombian paramilitaries and criminal gangs.
In recent weeks, Mr Maduro has closed several other border crossings and deported more than 1,000 Colombians.
Many Colombians have settled on the Venezuelan side of the border, married Venezuelans and had children there.
Having shut main frontier points in Tachira state last month, Mr Maduro also ordered the closing of the Paraguachon crossing in Zulia state to the north late on Monday.
The Venezuelan opposition says the border measures aim to heighten fears of a foreign enemy as a way of boosting the president's popularity.
The move follows an attack by smugglers in which three soldiers and a civilian were injured last month. Mr Maduro blamed the attack on right-wing paramilitaries from Colombia.
The 2,200km-long border (1,400 miles) between the two countries is porous and there has historically been a steady flow of people both ways.
But increasing price disparities between goods on either side of the border have generated a thriving smuggling business.
Venezuela's socialist government subsidises many basic food items and petrol in the oil-rich nation is extremely cheap.
Venezuela closed its border with Colombia for the first time last year.