Trump says Biden could have gone to slain NYPD cop Jonathan Diller's wake in 30 minutes and it wasn't 'rocket science' to call the grieving family before he went to his glitzy fundraiser

Donald Trump slammed Joe Biden for ignoring the wake of murdered NYPD officer Jonathan Diller even though he was only half an hour away.

The former Republican president also accused his Democrat rival of not backing the police because his liberal supporters 'won't let him'.

Trump attended the officer's wake on Thursday as Biden was also in New York for a political fundraising event with former Democrat presidents Barack Obama and Bill Clinton.

Trump told Fox News that Biden could have been at the wake 'within a half an hour depending on the mode of travel, they have some pretty fast travel.'

He went on: 'I think that politically he (Biden) can't support the police. I think he's also making a mistake, but I think politically his base won't let him support the police.'

Trump added; 'And I support the police, I would say at the highest level of any president by far, maybe double or triple.

'And they knew that that's why when I walked into that funeral parlor it was like love. It was just, they want to shy away from it.'

He said Biden and his team had not even called the family of the officer.

'They didn't even call the family,' he said. 'They could have called. You don't have to be a rocket scientist.'

But he added: 'I'm not sure they take his call.'

Officer Diller was shot and killed in Queens during a routine traffic stop on Monday and horrific surveillance footage captured the moment.

The married father of a one-year-old boy was shot in the stomach under his bulletproof vest after he and his partner stopped a car with career criminal Guy Rivera, 34, inside.

Rivera allegedly opened fire on Diller after he ordered the suspect to get out of the car.

In the footage three loud gunshots are heard ringing out as bystanders flee for safety.

Trump attended the wake at Massapequa Funeral Home on Long Island. 

The former president told Fox News: 'They're a great family the Diller family. We lost a hero really, the family is devastated, the police force is devastated. 

'It's happening more and more. It's really a lack of respect for law and order.'

We have to have law and order back in our country, we can't let this happen. This was a brutal murder. He was top of his class and everything perfect, beautiful record of doing his job properly and fairly, and this is what happens. It's just so horrible.

'Jonathan was the top in every respect, top of his class and this happened to somebody this should not have happened to. Ryan, the baby, one year old is never going to be the same, doesn't know yet what the meaning is but it's certainly going to have a big impact.'

Trump said as he was leaving the ceremony it felt like driving for miles with men and women in blue along the road.

He said: 'It was a long blue line. It was a long blue line indeed. And it's respect they have, respect for this family. They have respect for what Jonathan meant. And to me they're the most brave people.'

Trump added: 'It's getting getting worse and worse for police because we're not, we're not taking care of them, we're not allowing them to do their job properly.'