The Streatham attack was the second lone Islamist-related terror attack in London in the past three months.
Sudesh Amman, 20, was shot dead by police on Streatham High Road after stabbing three people in what police have called a terrorist incident.
It follows a similar attack in November when five people were stabbed, two fatally, near London Bridge.
The two incidents are notable because both attackers had fake explosives strapped to their bodies. Experts told Yahoo News UK the attacks could be examples of “suicide by cop”, in which terrorists deliberately behave in a threatening manner to force police officers to shoot them dead.
Dr Steve Hewitt, a senior lecturer at Birmingham University and expert on lone wolf terror attacks, says the idea of suicide by cop is an interesting one as London has now seen at least three Islamist attacks with fake suicide vests – including the previous London Bridge terror attack in June 2017.
The killers responsible for the 2017 attack all wore the vests, and their tactics seem to have influenced the later incidents.
Islam does not condone suicide, so the method is one way for Islamist attackers such as Sudesh Amman to seek “martyrdom”.
"Its use seems to be growing but it is far from a universal practice,” Dr Hewitt says. “It also speaks to the way that terrorists learn from the example of other terrorists.”
Dr Hewitt says the suicide by cop theory seems to make sense regarding why Islamic extremists carry out attacks in such a way, pointing out that, in contrast, most far-right lone actor attacks (Norway, Christchurch, the US, Quebec City, Darren Osborne in the UK) don't involve the death of the perpetrator.
He said there could be two other possible reasons for the use of the method, one being that it increases the fear factor and general panic among the public during an attack and "terrorists are obviously looking to generate fear".
It also potentially discourages bystanders from intervening out of fear that the suicide vest is real, so it could provide attackers with extra time to carry out attacks .
Dr Hewitt added: "Although in practice that does not seem to be the case so far."
Raffaello Pantucci, a senior associate fellow at RUSI, an independent think-tank on international defence and security, said attackers using fake devices is a very common phenomenon.
"They know they're going to die,” he said. “But they also want to inspire fear in the people you're attacking.
“If you look back at the Woolwich terror attack [in which soldier Lee Rigby was killed], when the police arrived, they charged armed officers with knives and a broken gun – the idea of using cops to die is not new.”
He also says that for terrorists it is a “guaranteed death”, and gives them the ability to attack more people because onlookers would be afraid to attack.
"There are materials that from Isis that say this is a good idea,” Pantucci said.
"We can see people who are copycatting each other. They see that this is what people [terrorists] are now doing. They seem to be emulating each other."