Two border guards were hurt when a group of 60 migrants tried to forcefully cross the border from Belarus, the Polish border guards office said on Monday.
The agency said in a statement the incident happened on Sunday evening near the village of Usnarz Grony.
They said a group of about 60 migrants "tried to force their way into Poland" wielding sticks and stones.
"One of the soldiers was hit by a foreigner with a branch in the face and another with a stone in the face. Both had to be taken to the hospital," the border guards office said. They have since been released.
Several other officers suffered minor injuries, according to the statement, but did not require medical assistance.
The statement was released alongside a video purported to show people attempting to pull the barbed-wire fence at the border with branches.
The border guards office claimed in its statement that some of the people present were "Belarusian soldiers in civilian clothes" and that they were cutting through the fence with scissors.
"The migrants did not manage to get to the Polish side," it added.
Poland has deployed 7,000 soldiers at its border area after declaring a state of emergency due to an influx of migrants.
Defence minister Marius Blaszczak announced on Monday that the number of troops in the area will be increased to 10,000.
According to Frontex, the EU's border agency, Poland saw 1,380 illegal crossings at its border with Belarus from January until September with most migrants coming from Iraq, Afghanistan and Russia. Latvia and Lithuania, which also share a border with Belarus, have also struggled with an influx of migrants, with the latter detecting 4,170 illegal crossings since the beginning of the year.
Most appear to be headed for Germany, which has also bolstered the number of officers at the border it shares with Poland to stem arrivals.
The EU has accused Minsk of facilitating illegal entry into the bloc to retaliate against sanctions imposed following the fraudulent August 2020 presidential election.
The three countries have called on Brussels to help fund a fence, which European Commission chief Ursula von der Leyen rejected last week.
The Polish state of emergency has been criticised by human rights NGOs which have been barred, alongside journalists, from entering the densely forested border area. They accuse Polish authorities of carrying out illegal push-backs.
At least eight people have died at the border area since this summer.