LONDON, March 23 (Xinhua) -- The re-opening of London's famous Westminster Bridge less than 24 hours after Britain's bad atrocity sent out a loud signal to extremists, experts said Thursday.
The Metropolitan Police in London named the terrorist as Khalid Masood, 52, who was born just outside London in the county of Kent, and lived in Birmingham, Britain's second biggest city.
He was shot and killed by armed officers as he attacked and killed an unarmed police officer, Keith Palmer, a married man aged 48.
Terrorism officers continued to interview a number of people while colleagues carried out intensive searches of properties in London and Birmingham.
As well as police officer Palmer, a London mother, an American and a 75-year-old man were killed after a car ploughed into a group of pedestrians on Westminster Bridge. Nearly 40 others were injured by the car.
And while the police activity continues behind the scenes, life in the British capital was getting back to normal.
Professor Gary Rawnsley, from the University of Aberystwyth in Wales, told Xinhua in an interview how lone-wolf attackers could cause the same degree of disruption, terror and fear as organized terrorism.
Rawnsley, an expert in international politics, said: "There has always been the possibility of such incidents in London, but such things are never inevitable until they happen.
"The nature of lone wolf terrorism is that it can happen anywhere, at the worst possible time in the worst possible place.
"Terrorism thrives on publicity, and that is one of the lessons we have had to learn in the past few years. One man, with a knife, driving a car can in an instant cause terror, fear and suspicion, all things terror groups thrive on.
"The media feeds into this by providing 24-hour coverage of such events around the world. We are living in a media age in which information and misinformation can be spread in seconds," Rawnsley said.
"Yet we cannot impose sanctions or limitations as that is not the way to defeat extremism. We need to become more aware of how we use media because of speed at which information is spread.
"We also need to send out signals to show our resilience, to let terrorists and extremists know that we won't be terrorised. We need that sort of stiff upper lip, rather than see everything closed down when terror strikes."
Professor Peter Neumann, director of the International Center for the Study of Radicalization (ICSR) at King's College London, said: "You can be a lone attacker but you can still be radicalised as part of networks as part of, for example, a Jihadist scene.
"I think even though it is true that people are communicating very widely and we even hear about people communicating with people in Syria," he said.
Dr Shiraz Maher, who also works at ICSR as deputy director said: "Unfortunately, we're seeing an increasing number of terrorist attacks in the West which use unsophisticated methods.
"These are plots that are very easy to construct, require little money, planning, and expertise, but which are nonetheless highly effective in causing death and destruction.
"We have already seen similar attacks in Nice and Florida, and the challenge for all of us is to now work out how we can identify and prevent these attacks before they occur," said Maher.