Counter terrorism police have launched an investigation after three improvised explosive devices were sent to buildings including London City Airport.

The packages – all A4-sized white postal bags containing yellow Jiffy bags - were assessed by specialist officers and found to contain small improvised explosive devices capable of starting a small fire after opening.

Officers are treating the incidents as linked and keeping an open mind about the possible motives.

Staff were evacuated after police were called to a report of a suspicious package at offices at City Aviation House, Royal Docks at about 12.10pm today.

Specialist officers made safe the device. The package was not opened and no one was injured. The building has since reopened.

As a precaution, DLR services to London City Airport were suspended but are now fully operational.

Flights to and from the hub were not affected.

The second package was opened by staff at the Compass Centre in Hounslow triggering the device which burnt part of the package.

No one was injured but the building was evacuated while officers made the device safe.

The building remains closed as enquiries continue. Flights from nearby Heathrow Airport were not affected.

In a third security alert British Transport Police were called to reports of a suspicious package in the post room at Waterloo Station at about 11.40am.

Officers attended and made the device safe. There were no injuries.

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.

The Met has issued advice to transport hubs across the capital warning them to be vigilant and report suspicious packages to police.

No arrests have been made. Enquiries are ongoing.