This large (18mm body and head) bug appeared in my office near the centre of Peterborough today. Checking on British Bugs it turns out to be an adventive species in the Coreidae (Squashbug) family. It is native to the western USA and first arrived in Europe in 1999. The last couple of years have seen increasing records in the UK but this could well be the first anywhere near here.
Not knowing what it was, I let it go, which sort of makes me a criminal apparently as it is against the law to release non-native animals. Fortunately you have to know what it is and it's taken me a while to get around to sorting out the ID.
Western Conifer Seed Bug Leptoglossus occidentalis
Canon Powershot A640