US veterans' support for NFL star Colin Kaepernick
US army veterans have sent messages of support to NFL quarterback Colin Kaepernick using the Twitter hashtag #VeteransForKaepernick.
The San Francisco 49ers player caused controversy when he refused to stand for the US national anthem during a pre-game ceremony. He said it was in protest against racial injustice.
His actions have sparked debate about respect, patriotism and the right of free speech, with Republican presidential candidate, Donald Trump, telling the player to quit the US and "find a country that works better for him".
The hashtag quickly began to trend with over 300,000 tweets using it so far.
Some veterans were keen to make the point that Mr Kaepernick was exercising his constitutional rights and that was what they had served to protect.
A common theme among some posts was that people should not speak on behalf of veterans in arguments about patriotism.
However, some US veterans have criticised the NFL quarterback for his actions.
A Facebook post by Senior Airman Brian Kolfage, who lost three limbs in Iraq in 2004, has been shared more than 30,000 times on Facebook.
Kelly Crigger, a retired lieutenant colonel, wrote an open letter to the NFL player for the veterans website We Are The Mighty saying "another professional athlete has decided to protest about the evils of the country that has given him more than any other country would".
Kaepernick said in an interview with USA Today: "I have great respect for the men and women that have fought for this country."
By Patrick Evans, BBC UGC and Social News team