(CNN) Muslim women linked arms along Westminster Bridge Sunday in a show of solidarity with the victims of last week's London terror attack.

The women, many of whom wore blue to symbolize peace, were joined by supporters who stood in silence for five minutes as Big Ben struck 4 p.m.

Four days prior, lone attacker Khalid Masood rammed a car into pedestrians on the bridge, killing three and leaving dozens injured.

He crashed the vehicle before later stabbing an on-duty police officer in the grounds of Parliament.

Masood was shot dead by police at the scene. A fourth victim died later in the week, when his life support was withdrawn.

The vigil, which was organized by the Women's March on London, came after a photo of a woman wearing an Islamic head covering crossing the bridge in the aftermath of the attack went viral on social media.

Some commentators criticized what they perceived to be the woman's indifference to an injured victim in the image.

Muslim woman pays no mind to the terror attack, casually walks by a dying man while checking phone#PrayForLondon #Westminster #BanIslam pic.twitter.com/B83Jwno65t — Texas Lone Star (@SouthLoneStar) March 22, 2017

'Sadness, fear and concern'

The woman in the photograph released a statement Friday to set the record straight.

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"Not only have I been devastated by witnessing the aftermath of a shocking and numbing terror attack, I've also had to deal with the shock of finding my picture plastered all over social media by those who could not look beyond my attire, who draw conclusions based on hate and xenophobia," she told Tell MAMA , a UK-based organization which monitors anti-Muslim attacks.

"My thoughts at that moment were one of sadness, fear, and concern," the unnamed woman said in a statement.

"What the image does not show is that I had talked to other witnesses to try and find out what was happening, to see if I could be of any help... My thoughts go out to all the victims and their families."

The photographer who took the photo has spoken out in the woman's defense.

"The people who took on that picture are being rather selective," freelance photographer Jamie Lorriman told Australian broadcaster ABC . "In the other picture in the sequence, she looks truly distraught... personally I think she looks distressed in both pictures."

Photos: Deadly attack outside UK Parliament A car is seen crashed into a fence outside the Parliament building in London on Wednesday, March 22. Police have launched a "full counter-terrorism investigation" after an attacker rammed a car into crowds of people and stabbed a police officer on Parliament grounds. Hide Caption 1 of 15 Photos: Deadly attack outside UK Parliament An armed police officer stands over the attacker, identified as Khalid Masood, outside Parliament. "It appeared that a car was coming towards the House of Commons mowing down pedestrians on the way," Member of Parliament Gerald Howarth told CNN. "The driver then got access to the parliamentary estate, stabbed a police officer and was shot." Hide Caption 2 of 15 Photos: Deadly attack outside UK Parliament Masood is treated by emergency services as police look on at the scene outside the Houses of Parliament. The Metropolitan Police say he was born in Kent, but is believed to have been living in the West Midlands recently. Police say Masood was also known by a number of aliases. "Masood was not the subject of any current investigations and there was no prior intelligence about his intent to mount a terrorist attack," Met Police said in a statement. Hide Caption 3 of 15 Photos: Deadly attack outside UK Parliament Member of Parliament Tobias Ellwood, in the glasses, tends to one of the injured people amid the chaos. The man the politician was trying to save was a police officer who died, a witness on the scene told CNN. Authorities identified the deceased officer as Keith Palmer, 48. Hide Caption 4 of 15 Photos: Deadly attack outside UK Parliament Emergency workers attend to injured people at the scene. Hide Caption 5 of 15 Photos: Deadly attack outside UK Parliament Medics treat a victim on Westminster Bridge. Hide Caption 6 of 15 Photos: Deadly attack outside UK Parliament People leave the Parliament building after the incident. Lawmakers were forced to remain in the main debating chamber of the House of Commons as police responded to the incident outside. Hide Caption 7 of 15 Photos: Deadly attack outside UK Parliament A person is treated at the scene. Hide Caption 8 of 15 Photos: Deadly attack outside UK Parliament Medical aid is provided outside Parliament. Hide Caption 9 of 15 Photos: Deadly attack outside UK Parliament Tourists were trapped for a time in cars on the London Eye Ferris wheel, which was stopped in the immediate aftermath of the attack. Hide Caption 10 of 15 Photos: Deadly attack outside UK Parliament A police officer stands guard near Westminster Bridge and the Houses of Parliament. Hide Caption 11 of 15 Photos: Deadly attack outside UK Parliament A person receives medical treatment at the scene. Hide Caption 12 of 15 Photos: Deadly attack outside UK Parliament At right, the car of British Prime Minister Theresa May is driven away from Parliament. Hide Caption 13 of 15 Photos: Deadly attack outside UK Parliament An air ambulance arrives at the scene. Hide Caption 14 of 15 Photos: Deadly attack outside UK Parliament Armed police enter the Houses of Parliament. Hide Caption 15 of 15

Another arrest made

In all, twelve people were arrested in relation to the attack. The latest was a 30-year old man who was detained Sunday in Birmingham "on suspicion of preparation of terrorist acts" under the TACT or Terrorism Act 2000, Metropolitan Police said.

Nine people who had been arrested earlier have been released "with no further action."

A 58-year-old man who was arrested Thursday in Birmingham remains in custody. A 32-year-old woman, arrested in Manchester, is out on bail, pending further inquiries.

Investigators: No direct ISIS link

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Khalid Masood was active on the encryption messaging service WhatsApp two minutes before he started his attack on Westminster Bridge, but no evidence has emerged to show he was communicating with ISIS at any point, the official told CNN.

Investigators are looking into communications he had with individuals leading up to the attack, the official added. But investigators currently believe Masood was more likely inspired by ISIS rather than directed by the terrorist group, the official told CNN.

Investigators are still assessing whether the attacker plotted alone or acted as part of a broader conspiracy. They're continuing to probe his contacts in radical circles in Birmingham, Luton and London, the official told CNN.

Investigation underway

Authorities are also investigating how Masood, who used multiple aliases, became radicalized. He was born Adrian Russell Ajao but also used the name Adrian Elms, police said Friday.

Born in Kent, Masood had previous convictions, including some for violent offenses, but none for terrorism, police said. His most recent conviction was in 2003 for possession of a knife.

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Attack victims

Victims, from left, American tourist Kurt Cochran, teacher Aysha Frade and police Officer Keith Palmer.

In addition to four deaths, last week's attack wounded at least 50 others, 31 of whom needed hospital treatment, Rowley said.

American tourist Kurt Cochran and college administrator Aysha Frade, a British citizen with Spanish roots, died Wednesday along with police constable Keith Palmer.

A fourth victim, Leslie Rhodes, 75, from Streatham in south London, died Thursday night after his life support was withdrawn, according to the Metropolitan Police.

Cochran and his wife, Melissa, from Utah, were visiting London to celebrate their 25th wedding anniversary when they were hit by the car on the bridge. Melissa suffered a broken leg, a broken rib and a cut to her head.

The couple ran a recording studio in West Bountiful, near Salt Lake City.

The Metropolitan Police issued a statement from their family Monday in which they said Melissa's health is improving.

"So many people have been so kind, and we are deeply touched by their goodness and generosity. Your notes, prayers, donations and love have helped us so much," they said.

"The most difficult part of all of this is that Kurt is no longer with us, and we miss him terribly. He was an amazing individual who loved everyone and tried to make the world a better place. He left a legacy of generosity and service that continues to inspire us.

"We are deeply saddened to lose him but are grateful that the world is coming to know him and be inspired by him."