Don Jr says his father won't stop fighting for America and blames the 'radical left' for shooting at Pennsylvania rally

• The former president's eldest son Don Jr said his father was in 'great spirits'
• resident Joe Biden: 'There's no place in America this kind of violence. It's sick.' READ MORE: Follow DailyMail.com's live blog for more details on the shooting 

Donald Trump's eldest son laid the blame for Saturday's rally shooting at the feet of the radical left but promised that it would not stop his father from campaigning.

It came hours after gunshots were fired at the former president during a rally in Pennsylvania, upending what was already an extraordinary campaign season.

Investigations continue but Donald Trump Jr. suggested there was no doubt who was behind the apparent assassination attempt. 

'I just spoke to my father on the phone and he is in great spirits,' he said. 

'He will never stop fighting to save America, no matter what the radical left throws at him.' 

Earlier, President Joe Biden spoke in front of the cameras to condemn the shooting. 

'There's no place in America this kind of violence. It's sick. It's sick,' he said.

'It's one of the reasons we have to unite this country.'

The former president was in full flight at his rally in Pennsylvania when shots were heard. 

Trump grabbed his right ear with his right hand, then brought his hand down to look at it before dropping to his knees behind the podium before Secret Service agents swarmed and covered him. 

More shots could be heard on the live video feed before the words 'shooter down.'

Trump got to his feet, with blood visible below his right ear. His red 'Make America Great Again' cap has been knocked off in the chaos.

But his supporters were cheered to see him raise a fist in defiance. 

The campaign was already historic, with a 78-year-old taking on an 81-year-old in a battle of the seniors.

Biden has been fighting for his political life after a stumbling debate performance in Atlanta, Georgia last month, taking the political scene into uncharted territory.

That was even before Trump's rally was interrupted by a gunman. 

The Biden campaign said it was suspending outgoing communications and was trying to pull TV adverts.