Updated 13.47

A CODED WARNING that there is a bomb threat to central London has been received by UK police.

Sky News is reporting that Scotland Yard have confirmed that a recognised code was received along with the threat, apparently from dissident republicans.

The warning came last night – just over a day before the British Queen’s planned visit to Ireland and a few hours after a disturbed manhole cover in central London sparked a security alert.

That alert saw the Mall and Carlton House Terrace near Buckingham Palace sealed off as the manhole cover was investigated. In another incident this morning, a suspicious bag was destroyed in a controlled explosion, according to the BBC. The bag, on Northumberland Avenue in London, is now not believed to have been a danger.

The bomb warning of yesterday evening was “non-specific” about the location or time of a potential threat.

The Metropolitan Police said it had received a warning of a threat to central London but the information did not include a specific location or time.

“A wide range of overt and covert tactics will continue to be used in London,” the department said. “Londoners should continue to go about their business as usual but we encourage the public to remain vigilant.”

A police official, who spoke on customary condition of anonymity in line with policy, said the warning related to a threat from a dissident Irish Republican terrorism group.

Parts of central London close to Buckingham Palace and government buildings were closed off to traffic, with a higher than usual number of police officers on the streets.

Police said no decision had been made to increase the country’s terrorism threat level as a result of the warning.

The AP reports that London Metropolitan police released a statement which said:

The threat level from Irish-related terrorism has not increased and remains at substantial — meaning that an attack is a strong possibility.