The IRA has claimed responsibility for three bombs sent to travel hubs including London City Airport.

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 on Tuesday (March 5).

Three packages – all A4-sized white postal bags containing yellow Jiffy bags - were discovered across the capital during the day. A fourth was identified at the University of Glasgow the following day.

A recognised codeword was used in the claim for responsibility allegedly made on behalf of the Irish Republican Army (IRA) to a media outlet in Northern Ireland on Monday.

Officers also confirmed the packages received last week were similar to devices sent in the past linked to dissident groups associated with Northern Ireland-related terrorism.

Those claiming responsibility have said five devices were sent but to date only four have been recovered.

Commander Clarke Jarrett from the Met said: “We are still keeping an open mind with regards who may be responsible and any possible motivation. Our utmost priority is to ensure the safety of the public and staff working with mail.”

The City Aviation House package was not opened and no one was injured. The building reopened after the device was made safe.

As a precaution, DLR services to London City Airport were suspended temporarily.

A London City Airport spokesman said: “Yesterday’s incident did not affect flights and passengers should continue with their travel plans as normal.

“As ever, our staff are on hand, alongside a visible Metropolitan Police presence.”

The second package was opened 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.

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 but cordons were in place.

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

No arrests have been made. Enquiries are ongoing.