A mob of runaway rheas which escaped a Norfolk farm three weeks ago are still on the loose – and now a woman is claiming to have seen one almost 30 miles away from where they first went missing.

Twelve rheas, which are large flightless birds distantly related to ostriches and emus, escaped from a farm near Stalham on June 21.

North Norfolk News: The rheas first went missing near StalhamThe rheas first went missing near Stalham (Image: Supplied)

Now, after three weeks on the run, a pensioner believes she saw one of the elusive birds in the village of Swanton Morley – almost 30 miles away from the farm.

Pensioner Nancy Briggs, 86, who lives in a bungalow at Woodgate Park, off Dereham Road, said she encountered one of the rheas when putting rubbish in her wheelie bin last week.

READ MORE: Norfolk villagers warned to lookout for gang of missing rheas

North Norfolk News: Nancy Briggs, 86, from Swanton MorleyNancy Briggs, 86, from Swanton Morley (Image: Adam Barker)

“I went outside at dusk one night when I saw the bird walking down the street,” Mrs Briggs said.

“I was surprised to see it stood around 20 metres away from my front door.

“My dog, Holly, who’s a 15-year-old black Labrador, stood there watching it walking down the street like it owned the place.

“I was anxious she was going to run towards it, so I put her inside. When I came back out the bird had disappeared.”

READ MORE: Missing rheas escape Stalham farm and head to Norfolk coast

North Norfolk News: Where Nancy Briggs, 86, from Swanton Morley, claims to have spotted the rheaWhere Nancy Briggs, 86, from Swanton Morley, claims to have spotted the rhea (Image: Adam Barker)

However, wildlife expert Kevin Murphy, of Norfolk Wildlife Rescue, said although it is possible that the birds had travelled that far in three weeks it is “highly unlikely” due to the distance and number of roads.

Some of the missing rheas have been rescued, but it is unknown how many are still out there.

The birds, which are native to South America, can grow up to five foot tall and run at speeds up to 50mph.

They were believed to have forced their way out of their enclosure at the farm, with people in Lyndford Road, Stalham, waking up to them in their gardens and marauding through the streets in the early hours of the morning they escaped.

North Norfolk News: Nancy Briggs Nancy Briggs (Image: Adam Barker)