UK police warned of bomb in central London

LONDON, (Reuters) – British police said today  they had been warned of a bomb in central London, a day before  Queen Elizabeth makes a historic visit to Ireland.
Media reports said the coded warning came from dissident  republicans opposed to the Northern Ireland peace process.
The threat comes on the eve of the first visit to Ireland by  a British monarch in a century and a week before U.S. President  Barack Obama makes a state visit to London.
“A bomb threat warning has been received relating to central  London today. The threat is not specific in relation to location  or time,” London police said in a statement.
The police advised Londoners to go about their business as  usual but to remain vigilant.
“The threat level from Irish-related terrorism has not  increased and remains at substantial, meaning that an attack is  a strong possibility,” it said.
Police said earlier that a security alert had led to the  closure of the Mall, a broad avenue leading to Buckingham  Palace, Queen Elizabeth’s residence, but refused to say what had  prompted it.
In a separate incident, police carried out a controlled  explosion to destroy a suspicious bag in a central London  street, although it turned out to be harmless, a police  spokesman said.
Militant groups opposed to British control of Northern  Ireland are the biggest risk during the queen’s four-day visit  to Ireland, which will be surrounded by intense security.
A 1998 deal ending Irish nationalists’ guerrilla war against  British rule of Northern Ireland set the clock ticking on a royal  visit but it was not until police and justice powers were  transferred from London to Belfast last year, the last piece of  devolution, that the diplomatic wheels could be set in motion.