The dogs, reportedly named Marshall and Millions, were shot dead by an armed police officer at 5pm on Sunday by the Limehouse Cut.
Louie Turnbull’s dogs had allegedly attacked a woman and her dog on Sunday afternoon in Commercial Road, Limehouse.
Footage posted on social media showed officers then pursued Mr Turnbull, who was holding the two dogs on a short lead along the canal, on Sunday afternoon.
The situation then appeared to become heated, as he was tasered to the floor and the animals were shot dead.
Two complaints about the fatal shooting of the dogs are being assessed by police watchdog the Independent Office for Police Conduct.
A petition, organised by rescue dog handler Sadie Geoghegan-Dann, hit 100,000 signatures on Thursday.
The dog trainer claims horrific video footage portraying the shooting clearly shows “both dogs on leads, both under control”.
She tweeted: “My petition is picking up pace - please sign and share to bring criminal charges against the Met Police officers who inhumanely and unjustifiably shot and killed two dogs in East London on Sunday. Video evidence shows both on leads, both under control.”
In the petition, approaching its target of 150,000, she wrote: “The Metropolitan Police are attempting to justify the barbaric killing of two dogs in Tower Hamlets, London.
“Why is it acceptable for the police to not only Taser their owner, but shoot and kill both dogs at close range?! One of which seemingly doesn’t die straight away, either, and is left to suffer on the canal path while shocked onlookers are left screaming.
“And why, too, does one police officer, who has one of the dogs secure in a catch pole, then choose to release that dog and let it run back to its owner, only to be shot as it runs away?”
It came as Sadiq Khan told LBC on Thursday that he found it “distressing” to view the video footage of the dogs being shot dead.
Asked by a caller why a “homeless” man had been Tasered and had his two “beautiful” dogs shot by police despite them apparently being on a lead, the mayor said he only knew what he had read or seen in the media.
The caller, Nick from Slough, claimed the dogs “posed no risk” and said their tails were wagging, showing they were “happy and calm”.
Mr Khan, who has a pet golden Labrador, Luna, replied: “It is distressing. You don’t have to be a dog owner like me or you to be distressed by this.
“The police watchdog, the IOPC, is now looking into this. It’s important they look into this because there was a legal discharge of a gun. The man who was the dog owner was arrested as well.
“We have only seen what we have seen. I think we should wait and see for the IOPC to do their report, but of course it’s distressing for those of us who watched this.”
Mr Khan added: “It’s really important that we also accept that those of us who have watched this and are distressed by it don’t know the full story.
“The IOPC understand there is a huge public interest. The IOPC also understand that police officers on a daily basis are making split-second decisions. I would hope the IOPC wouldn’t take months and months in relation to this investigation.”
Mr Turnbull, 46, of no fixed address, was charged on Tuesday with being the owner of a dog that was dangerously out of control and being in possession or custody of a dog while disqualified from owning or keeping a dog.
He appeared in custody at Thames Magistrates’ Court.
In a statement, a Met spokesperson said: “Officers attended the location where the aggressive behaviour of two dogs was of considerable concern and posed a significant threat to them.
“A man was arrested in connection with the incident for having a dog dangerously out of control and assault offences. He has been taken into police custody.”
The statement added a Taser was discharged during the incident and both dogs “were destroyed by police at the scene” but no-one was taken to hospital.
A Met statement said: ”This is never an easy decision for an officer to take, but police have a duty to act where necessary before any further injury is caused.”
The Met’s directorate of professional standards reviewed the incident, including all of the available body-worn camera footage, and was “satisfied that there are no concerns around officer conduct”, the force added.
Scotland Yard has been approached for further comment.
