A mum-of-two from Erith has spoken of her terror when armed police allegedly stormed a Tesco Express store she was in with her children.

Claire Machin, who lives next door to Tesco in Northend Road, described the incident on Tuesday afternoon at 4pm as "the worst thing I have ever experienced in my life" as she feared for the safety of her seven-year-old son.

While Claire stood at the checkout with her two-year-old daughter in the pram and talked to her friend, her son was standing by the door of Tesco when she claims about 13 armed police officers ran inside.

"They were pointing the guns in our faces - obviously they weren't meaning to shoot - but having a gun pointed in your face is scary.

"[The officer] was screaming at me 'where is the man in the red shirt?'"

She added the officer asked her the question about six times before she said she did not know what they were talking about.

Amid reports a man carrying a shotgun was on the loose, Ms Machin said she did not see the suspect holding a weapon when he was arrested, but said she saw officers pin a teenager in a red T-shirt up against the wall.

Despite the chaos of the incident, which "seemed to last for hours", Ms Machin said her only concern was for her son, who tried to hide during the ambush.

"My poor little boy was subjected to this and he suffers from anxiety," she said, adding his nervous ticks seem to have got worse in the days since.

"We could touch their guns, they were that close to us. I just wanted to get my little boy home," she added.

However, Ms Machin did praise the Met Police for offering support after the incident, suggesting an officer could visit her son to explain he was not in any danger.

Tesco Express in Erith has confirmed the store was shut due to a police incident on Tuesday afternoon.

A Met Police spokeswoman confirmed: "Detectives investigating an incident that took place in Lower Road, Belvedere, at 15:30hrs on Tuesday, 25 September have charged a teenager.

"A 16-year-old male was charged on Wednesday, 26 September with taking a motor vehicle without the owner’s consent, driving while disqualified, driving otherwise in accordance with a licence and driving without insurance.

"He appeared in custody at Bromley Magistrates’ Court on Thursday, 27 September.

"He has been bailed to appear at the same court on 12 November for a trial."

News Shopper understands the arrest was made in relation to reports of an armed robbery in Belvedere, during which a man in his 60s was threatened with what was believed to be a firearm.

Police pursued a suspect to Northend Road in Erith, where he was arrested.

Another man believed to be involved has not been found. 

He is described as a white man aged 25-30, of medium build and with dark hair.

Anyone with information about the incident is urged to call Bexley CID on 101 quoting CAD 4555/25SEP or Crimestoppers anonymously on 0800 555 111.