Royal Mail investigates if staff ate cannabis brownies at Clapham office

A video appearing to show postal workers struggling to stand emerged on Tuesday

Royal Mail staff who allegedly got high after accidentally eating cannabis-laced "hash brownies" from an unclaimed parcel are being investigated.

A video of the incident appears to show postal workers struggling to stand after eating the cakes at a sorting office in Clapham, south London.

One voice could be heard appearing to say: "I think it's weed".

Royal Mail said it was taking the matter very seriously and it "expects the highest standards of behaviour".

"We have commenced an investigation, which will determine whether any further action, including disciplinary action, might be taken.

"We are also reminding all staff at the delivery office of the correct procedures for dealing with items with no address for delivery or return."