Police are hunting for three men captured on CCTV after an 82-year-old man was violently robbed.
Three attackers pinned Ahmet Dobran to the ground, repeatedly beating him on his back and arms before robbing him of his jewellery.
Mr Dobran suffered three fractures to his vertebrae and he now remains in an induced coma following the attack on Sussex Road in Barking.
The attack aggravated his Parkinson's and cancer and he is now only able to breathe via a tracheotomy.
His family have said he would now be housebound for the rest of his life and unable to fly to Cyprus to see his relatives.
The attackers took his gold bracelet and Longine wristwatch.
Scotland Yard have released CCTV images of three men who detectives say are wanted for questioning in connection with the attack, and have also appealed for witnesses to come forward.
The men can be seen running down a street in the pictures. Two of them appear to be grinning.
PC Sam Bush, the investigating officer, said: "How three grown men can be so vicious in attacking and robbing an 82-year-old man with a walking stick is beyond comprehension. He was out shopping at the time of the attack and had bags of shopping in his hands, which made him even more vulnerable.
"The callous men who attacked Ahmet swore at him throughout the attack. He is understandably in a state of shock and in a serious but stable condition in hospital. We need to catch these vicious thugs before they target anyone else as they clearly have utter disregard for their victims and do not hesitate to use violence."
In a statement to police, the son and daughters of Mr Dobran said: "We are all devastated by it all. This attack has taken his independence away. Our father is not an indoor person, and now he will be stuck in doors for the rest of his life. We are appalled at how someone can do this to an old man.
“He is now unable to fly to Cyprus to see the rest of his family, he used to go there a couple of times a year.
“Can someone please come forward with information regarding who done this to our father, someone knows who they are. The people who did this could do this to someone else, with no guilty conscience."
Anyone who recognises the men pictured is urged to call police on 101 or Crimestoppers anonymously via 0800 555 111
