Investigation in suspicious packages case is ongoing: Scotland Yard

Scotland Yard on Wednesday said its Counter-Terrorism Command investigation into three suspicious packages delivered to some of London's major transport hubs is ongoing, with one line of inquiry trying to establish if the incidents have a link with Ireland. The devices, categorised by the Metropolitan Police as improvised explosives, were delivered to buildings near Heathrow Airport, Waterloo Station and London City Airport on Tuesday.

One of the packages triggered a mild explosion, while the others were disabled by specialist officers in incidents that occurred at different times of the day on Tuesday and were classed as "linked series" by counter-terrorism officers. "We are pursuing a number of lines of enquiry. One such line is the possibility that the packages have come from Ireland," said Commander Clarke Jarrett, head of the Met Police Counter Terrorism Command.

"We quickly shared images of the packages with staff at transport hubs and mail handling companies and offices, to aid them in identifying similar packages, however, we have not received any further reports," he said. The Met Police said its specially-trained Project Servator officers, who carry out operations every day, will be present at some transport hubs across London as a precautionary measure.

The officers will be both plain clothes and uniform and are specially trained to identify tell-tale signs that someone is in an area for terrorist or other criminal purposes, the Met Police said. "We have issued extensive advice to transport hubs and mail sorting companies to be vigilant for and report suspicious packages to police, as always we encourage anyone who sees something suspicious to report it," added Jarrett.

The packages – all A4-sized white postal bags containing small yellow bags – were assessed by specialist officers as capable of igniting a small fire when opened. According to images released by the police, the packages had Republic of Ireland stamps and a “return to sender” entry referring to the Irish capital of Dublin, leading to speculation that Ireland-related terrorist groups may be involved in the incidents. The Gardai, Ireland's police force, confirmed it was assisting the Met Police with its inquiries. There are fears that pro-Republicans, who have historically been against Northern Ireland being aligned to the UK, may be behind the incidents.

There have been similar letter-bomb incidents involving Irish dissidents in Britain and Northern Ireland in 2013 and 2014. While the devices did not affect air or rail services, workers were evacuated from City Aviation House at City Airport and Heathrow's Compass Centre, where the packages were sent.

Both have since reopened, although workers have been told to be vigilant for further suspicious packages.

(With inputs from agencies.)