The men are joined by three British veterans and a German, all of whom are NATO-trained and ready to assist the Ukrainian territorial defense teams.
Some US special ops veterans have joined the fight against Russia's invasion of Ukraine.
Six American special ops veterans are currently on the Polish border, according to Dailymail.
The report said the ops veterans are ready to enter Ukraine and join the resistance against Putin's army after a call for help from President Zelensky.
The men are joined by three British veterans and a German, all of whom are NATO-trained and ready to assist the Ukrainian territorial defense teams.
They are believed to be among the first to join the newly former International Legion of the Territorial Defense of Ukraine that Zelensky announced on Sunday after a weekend of staving off the enemy.
BuzzFeed News cites an unnamed US Army veteran recruiter who said there are also two former US infantry officers ready to fly to the region to provide leadership for the group.
They will join sixty British volunteers who are also planning to make their way to Ukraine to help the fight.
Those former Army and Special Forces soldiers have been gathered by Mamuka Mamulashvili, 43, commander of the Georgian National Legion.
It is unclear if he also recruited the ten NATO troops who are already on the Polish border.
British Foreign Secretary Liz Truss said on Sunday the UK would back Britons if they travelled to join the resistance movement who are bravely repelling the Russian forces.