Artefacts Left on Train in Durham

British Transport Police are looking for an individual who took a bag left by a passenger from London who forgot to take it when they left the train in Durham. The bag contained a Late Medieval ring and a Late Roman fibula (BBC Ring and brooch 'treasures' taken from Edinburgh-bound train 20th Nov 2019):

Police said the items, valued at £1,000 and £500, were taken from an Edinburgh-bound service travelling from Durham. The rare jewellery was left in a red plastic bag in the overhead locker by a passenger who disembarked at Durham. However, the items were not handed into lost property and are now presumed stolen, said British Transport Police. The medieval ring, which was left with the brooch in a red plastic Aldi bag, has the inscription "o mi hart is yovrs" (oh my heart is yours) on its inside. The passenger who left the items was travelling from London to Durham on an Edinburgh-bound service. The jewellery is thought to have been taken sometime between the evening of 4 October and 12.30 on Saturday 5 October. Anyone with information is asked to contact the British Transport Police.

The ring was recorded by the PAS: DUR-05020D on Weds Oct 24th 2018 (Treasure case 2018T790). The brooch was also recorded by the Durham FLO (on Monday 18th June 2018, DUR-7DDAA3, Treasure case 2018T429). Interestingly, both records were 'updated' Monday 18th November 2019 - but not with the information that they'd been stolen. The photos used in the article are attributed to the Transport Police, but are in fact PAS photos. It seems a lot of the details are (deliberately?) fogged. How did the person with the red plastic Aldi bag come by these artefacts? The PAS has in the past used orange plastic Sainsbury's bags.