South Yarra dog theft: Owners' desperate plea for return of chihuahua after he was nabbed by heartless thieves in Melbourne

The distraught owners of sick chihuahua have issued desperate plea to the heartless thieves who stole their beloved pet and have offered a reward for his return.

Thieves nabbed an Uber van hired by Luke Renfrew and Rhys Habermann while moving house in the inner Melbourne suburb of South Yarra on Thursday night.

CCTV captured the moment the opportunistic thieves climbed into the van and sped off with the men's chihuahua Diesel still inside the vehicle.

Uber tracked the van for a kilometre before the thieves disabled the GPS device.

Diesel's owners are frantically worried about their ailing pet, who suffers a neurological condition and needs regular medicine.

'Someone just took the car,' one of Diesel's owners shouted.

'Are you serious?' asked the other man.

'And the dog, what the f**k?' the first man exclaims. 

The men told Seven News the loss of their beloved pet has left them in deep distress. 

 'I feel sick,' Mr Renfrew said.

'I think I’ve had two hours sleep in three days.'

Mr Habermann said that he was 'devastated' and had been crying for the last two days.

The men have offered a reward for anyone able to help them find Diesel amid growing concerns about the dog's deteriorating health.

'If he doesn’t have the medication he gets quite sick for 48 hours,' Mr Habermann said.

Mr Renfrew said even if the thieves are the ones to return Diesel, charges won't be pursued. 

'We don’t care about the van, we just want our dog back,' he said.