Three men armed with knives and disguised in balaclavas broke into a children's birthday party in Norwich and demanded drugs on Friday evening.

At about 6.50pm, the men broke into the home in Hunter Road, Catton Grove, but were confronted with a family and young children celebrating a birthday.

The men demanded drugs before robbing a woman inside the property of her phone.

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A manhunt was launched as police 'flooded' the area after the incident, but no arrests have yet been made.

Duty inspector Graham Dalton of Norfolk Police said the men may have targeted the wrong house.

'We suspect these are Gravity offenders because they were asking for drugs when they went into the address,' he said.

'That is really sad especially as there were some children in the address.'

Posts have been circulating on social media since the incident, but police have moved to reassure residents this was a 'one-off' attack.

It is not being linked to a home invasion and attempted robbery carried out in the city on Wednesday.

'It is a one-off for this specific incident, and we are treating it as unconnected to other crimes in Norwich earlier this week,' added Insp Dalton.

'We did flood the area to try to look for the suspects but unfortunately we didn't manage to locate them. We have enquiries ongoing locally, including CCTV.'

He said it must have been 'very distressing' for those involved, and moved to reassure victims and those living nearby that officers were doing 'everything we can to find the offenders quickly'.

And he added: 'If anyone has any information as to why this property may have been targeted please get in touch.'

The victims were 'shaken' but uninjured.

All three men are described as black, two were around 6ft tall and one was slightly shorter. All were wearing dark clothes and balaclavas.

Anyone with any information should contact Norwich CID on 101. Alternatively information can be left with Crimestoppers on 0800 555111