Washington: Sarah Palin’s son was arrested on domestic violence charges after an armed altercation with his girlfriend, according to court documents filed Tuesday as his diehard Republican mother endorsed bombastic presidential nominee Donald Trump.

During the fight, Track Palin allegedly brandished a rifle and threatened to shoot himself, according to the documents that come the same day Sarah Palin, a 2008 vice presidential nominee, former Alaska governor and gun enthusiast, endorsed Trump’s quest for the presidency.

Track, 26, Palin’s eldest son and an army veteran who served a tour of duty in Iraq, was arraigned in a pre-trial facility in Alaska, the Anchorage Daily News reported.

According to the documents filed in court and posted online, Track got in a drunken fight with his girlfriend at his mother’s house in Wasilla, Alaska late Monday.

The girlfriend called 911 ‘reporting that a male had punched her in the face and that a firearm was involved,’ according to the police affidavit filed in court.

Soon after, a man who identified himself as Track Palin called 911 to report that the female caller was drunk.

When police arrived they interviewed Track Palin, who ‘was uncooperative, belligerent and evasive’ to questions. His right eye was injured, and he had ‘a strong odor of alcohol on his breath and person.’

Police could not find the female caller, and ‘due to Palin’s escalating hostility... Palin was placed into handcuffs.’

Soon after officers found the girlfriend upstairs hiding under a bed.

‘She was visibly distraught and [had an] injury to her head,’ the documents said.

Palin eventually told police that he and the woman had been arguing most of the night over her alleged contact with a former boyfriend.

According to the affidavit, the woman said that Palin ‘struck her on the left side of her head near her eye with a closed fist,’ and when she curled up in the fetal position on the ground he kicked her on the right knee.

Palin threw the woman’s mobile phone across the driveway, and after she retrieved it he was holding a gun pointed near his face, yelling ‘do you think I won’t do it?’

The woman ‘was concerned that he would shoot himself and ran outside and around the house,’ and later hid under a bed upstairs.

Upon inspection police found ‘the involved firearm, an unloaded AR-15 rifle,’ on the kitchen counter.

Track Palin faces charges of domestic violence assault, interfering with a report of domestic violence, and weapons misconduct.