Police are investigating after three small improvised explosive devices were found at buildings at Heathrow Airport, London City Airport and Waterloo train station

All the packages were A4-sized white postal bags containing yellow Jiffy bags and appeared capable of igniting a small fire when opened, police said.

Scotland Yard said officers are treating the incidents as linked and are keeping an open mind regarding motives.

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No one has been injured in the three incidents, police said.

The Metropolitan Police Counter Terrorism Command said was being treated as a "linked series"

Specialist officers were called to Waterloo Station, Heathrow Airport and London City Airport in separate incidents between 09.55am and 12.10pm on Tuesday.

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In a statement, Scotland Yard said: "The Met Police Counter Terrorism Command has launched an investigation after three suspicious packages were received at buildings in London today, Tuesday, 5 March.

"The packages have been assessed by specialist officers to be small improvised explosive devices. 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.

"At approximately 9.55am the Met Police received a report of a suspicious package at The Compass Centre, Nelson Road, Hounslow. The package was opened by staff at the building, causing the device to initiate. This resulted in part of the package burning.

"No one was injured. The building was evacuated as a precaution. Specialist officers attended and made the device safe. The building remains closed as enquiries continue. The building is not based at Heathrow Airport, and flights have not been effected by this incident.

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"At approximately 11.40am British Transport Police were called to reports of a suspicious package in the post room at Waterloo Station. The package was not opened. Specialist officers attended and made the device safe. No one was injured.

"The station was not evacuated however cordons are in place at a small area outside the station on Cab Road. Train services are continuing to operate as normal.

"At approximately 12.10pm police were called to a report of a suspicious package at offices at City Aviation House, Royal Docks, Newham. Staff were evacuated from the building as a precaution. The package was not opened and no one was injured. Specialist officers attended and made safe the device. The building has been reopened.

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"As a precaution, DLR services to London City Airport were suspended but are now fully operational. Flights to and from the airport have not been affected.
"The Met Police has issued advice to transport hubs across London to be vigilant for and report suspicious packages to police.

"No arrests have been made.

"Enquiries are ongoing."