Police believe that suspect arrested after a mum and daughter were stabbed in Leicester Square did not know the pair.

Emergency services were called to the scene at 11.34am today (Monday, August 12) where a girl, aged 11, was found with stab wounds.

She was taken to hospital where it has been assessed that she is seriously injured and will need further treatment, but her condition is not life-threatening.

Her mum, aged 34, suffered minor injuries.

A 32-year-old man was arrested at the scene.

No one else is being searched for in connection with the attack and police have said they do not believe the suspect and victims knew each other.

An investigation has now been launched.

Witnesses, or anyone with footage or photos of the incident, are asked to call 101 or to contact Crimestoppers, anonymously, on 0800 555 111, giving the reference 2745/12AUG.

Detective Chief Superintendent Christina Jessah, in charge of policing for Westminster, said: “This is a horrific incident and our thoughts are with the victims and their family.

“We will continue to provide support to them over the coming days and weeks.

“I would like to pay tribute to the members of the public, including staff from local businesses, who bravely intervened in this incident.

“They put themselves at risk and showed the best of London in doing so.

“An urgent investigation is now ongoing and detectives are working to establish the details around exactly what happened.

“At this stage we don’t believe the suspect and the victims were known to each other.

“While we continue to work to establish the suspect’s motive, at this stage there is nothing to indicate the attack was terror-related.

“Detectives will be keen to speak to anyone who was in the area and may have information that can assist with their enquiries.

“I would urge anyone who can help to get in touch.”

A man who works opposite the scene, and who did not want to be identified, said he saw the suspect earlier in the day.

He said: “He was standing, doing nothing, eating and talking to himself as I saw.”

He filmed a man being arrested outside the TWG Tea shop and said he recognised him from the morning.

The footage, seen by the PA news agency, showed police detaining a white, skinny man wearing a black T-shirt with white text on, and dark trousers.

He added that the woman who was injured was standing before the ambulance arrived, but he did not see the girl.

The witness, who gave his name as Desmond, 45, said the knifeman focused the attack on the girl, putting her in a headlock and stabbing her.

Desmond, 45, who performs as Darth Vader on the square “every day”, told reporters: “When I looked to my side I saw a young man… was stabbing her several (times) with a knife.

“Before I could jump down to go (over there), two guys were just passing, and they grab him, they put him on the ground, and immediately the police came.

"I think the woman was also stabbed once, but the child was the most targeted, he was stabbing the child several times. Police held him and stood him up and cuffed him.”

Desmond said the woman and girl appeared to be family or known to each other as they had been together before the attack happened.

He added: “It was so terrible, I’ve never seen a thing like that. I was heartbroken, I saw the woman was screaming with all her strength.”

A security guard said he “jumped on” and took a knife from a man who stabbed a child in Leicester Square.

The guard, who gave his name as Abdullah, 29, said he had worked in security at the TWG Tea shop for the past “seven to eight months”.

Abdullah told the PA news agency: “I heard a scream, at that moment I saw there was one person, roughly (in their) mid-30s or early 30s, and he was like stabbing a kid – I jumped on him, held the hand in which he was (carrying) a knife, and just put him down on the floor and just held him and took the knife away from him.

“Then a couple of more people joined as well, and we just held him until the police came, it took maybe three to four minutes for the police to arrive and then they just took him into custody.”

He and his colleagues gave first aid to the child before the police joined in, he said.

“I just saw a kid getting stabbed and I just tried to save her. It’s my duty to just save them.”

He added that he did not know if the girl was with family members at the time.