The flight was from Bogata. Did someone mention drugs??? Those flights are descended upon by customs when they arrive, so it was probably during a routine check.
Just missed all the hoo-ha, as I left my office (which is near the South Terminal) just before 5pm. Only odd thing I noticed was a police van at the junction (which there seemed to be a post van, so I thought it was just broken down). Only found out about the LGW stuff when I got home.