Three parcel bombs have been discovered at Heathrow Airport, London City Airport and Waterloo railway station in what is believed to be a coordinated attack. 

Gardaí (Irish police) are assisting Metropolitan Police after three package bombs were discovered in London which may have been sent from the Republic of Ireland. The parcels were found at Heathrow Airport, London City Airport and Waterloo railway station in what police believe was a coordinated attack. 

Initial images of the parcels appear to show that they were sent from the Republic of Ireland with a sender's address in Dublin. 

Photo of one of the suspect devices - this one sent to Heathrow. It caught fire: pic.twitter.com/keObgokRVH

— Alistair Bunkall (@AliBunkallSKY) March 5, 2019

"We are assisting the Metropolitan Police with their enquiries," said a Garda spokesperson. 

English police have not yet ruled out the possibility of other parcel bombs appearing and have issued advice around transport hubs in London “ to be vigilant for and report suspicious packages to police.”

Gardai confirm they are assisting UK terror police after "small improvised explosive devices" were sent to major London transport hubs using Irish stamps: https://t.co/tamRhgfcro pic.twitter.com/UAVM6QeKjn

— Newstalk (@NewstalkFM) March 5, 2019

“The packages – all A4-sized white postal bags containing yellow Jiffy bags - have been assessed by specialist officers to be small improvised explosive devices,” a spokesperson said. 

“These devices, at this early stage of the investigation, appear capable of igniting an initially small fire when opened.

“The Met Police Counter Terrorism Command is treating the incidents as a linked series and is keeping an open mind regarding motives.”

Look closely at the stamps: they say Eire on. Rep of Ireland.

— Alistair Bunkall (@AliBunkallSKY) March 5, 2019

Photos of two of the parcels show a limited edition Valentine's Day stamp created by An Post, Ireland's postal service. 

A spokesperson has not commented on a motive behind the packages. 

Guinness-march2019

A security personnel stands guard outside a police cordon at Waterloo Station, central London on March 5, 2019, following a report of a suspicious package at the station.TOLGA AKMEN/AFP/Getty Images