Hungary said Friday it had increased the number of soldiers building its controversial anti-migrant border fence to 3,800, as the numbers of people crossing from Serbia hit a new record.
The soldiers "are in the southern border sector with a priority task to build the fence," said Defence Minister Istvan Simicsko, appointed this week to speed up construction of the barrier.
Hungary wants to speed up construction of its four-metre-high (13-foot-high) fence along its border with Serbia as it struggles to cope with huge numbers of migrants travelling up from Greece and the Balkans.
Despite laying razor wire along its 175-kilometre (120-mile) frontier late last month, police said 3,601 migrants entered Hungary on Thursday, beating the previous record of 3,321 set two days earlier.
Delays in building the fence, which has drawn criticism from across Europe, are widely thought to have led to the resignation on Monday of the previous defence minister.
The government aims to complete its construction by late October or early November.
It was unclear how many soldiers were engaged in building the fence before Friday's announcement, but since Wednesday there has been a large-scale mobilisation of troops, a source told AFP.
Dozens of troop carrier vehicles were reportedly seen heading south on the M5 motorway towards the border throughout Thursday. On Wednesday the army began military exercises in the area.
For now the Hungarian army is only engaged in building the fence but under new legislation, from September 15 it will also be engaged in processing asylum applications and manning processing points.
Later this month parliament will also vote on beefing up the powers of the police and army, including giving troops the authorisation to use arms in emergency situations.
Some 8,000 migrants are thought to have crossed at the border post of Nickelsdorf between Austria and Hungary on Thursday, and a further 3,600 were recorded overnight by Austrian police.
The cross-border motorway was again closed to cars on Friday morning due to the huge numbers of refugees walking along it.
Austria's rail operator suspended services to Hungary on Thursday due to "massive overcrowding" but regular trains were still running towards Germany.