"The defence minister decided to send technical equipment to search the area in order to determine whether a train actually exists," Defence Ministry spokesman Jacek Sonta told AFP.
"The army is acting at the request of the governor of the region concerned," he added.
On Monday Tomasz Smolarz, governor of the southwestern region of Lower Silesia, said it was "impossible to claim that such a find actually exists at the location indicated based on the documents that have been submitted."
This comes just days after a senior culture ministry officials said on Friday he was "more than 99 percent sure" an armoured railway carriage had been found based on ground-penetrating radar images.
But according to Smolarz, no such images had been submitted to authorities.
Police blocked off the presumed location of the train along a stretch of active railway tracks on Monday in a bid to prevent accidents as a curious public swamps the area near the city of Walbrych.
A Polish NGO on Monday filed a complaint with state prosecutors against Piotr Zuchowski, a secretary of state at the culture ministry, for unfounded claims about the existence of the train that have lead to considerable public funds being wasted on securing the area concerned.
Global media have become fascinated by the prospect of a railway car full of jewels and gold stolen by the Nazis after two men - a German and a Pole - claimed to have found an armoured train car containing valuables, precious metals and industrial materials.
The World Jewish Congress has asked that any valuables found that once belonged to victims of the Holocaust should be returned to their owners or heirs.
Zuchowski also claimed that someone who had been involved in hiding the train, presumed to be over 100 metres (330 feet) in length, had disclosed its location before dying.
Rumours of two special Nazi trains that disappeared in the spring of 1945, towards the end of World War II, have been circulating for years, capturing the imagination of countless treasure-hunters.
The lore is fuelled by a massive network of secret underground tunnels near Walbrzych - including around the massive Ksiaz Castle - that Nazi Germany built and where legend has it the Third Reich stashed looted valuables.