British radio stations today begin broadcasting commercials urging the public there to look out for suspicious packages as police warned that dissident republicans could be plotting bombings in the run-up to the June 7th general election.
Police said dissidents, including the "Real IRA", represented a "graver danger" than March's explosion at the BBC and could attempt a bomb of similar proportions to the Omagh attack.
Assistant Commissioner of Specialist Operations Mr David Veness said: "One looks in sheer horror at the impact of Omagh with all the death and tragedy that it caused - that remains the most significant challenge that this particular grouping represents."
Terrorist attacks escalated at the time of the 1992 and 1997 British general elections, he said, and experts fear the pattern will be repeated in the run-up to June 7th.
The Metropolitan Police's counter-terrorist advertising campaign is its second in six months.
Six London radio stations will carry the commercial from today until the end of electioneering, warning people to report anything suspicious and urging landlords and car dealers to be vigilant about their tenants and customers.
The campaign features two commercials, dramatising a scenario of a suspicious package being found in a shopping centre and on a train.
Police believe terrorists are securing munitions from "readily available" sources in eastern Europe and are keeping an open mind as to whether a "Real IRA" cell is based in the capital.
PA