London — Libyan-sponsored terrorism has returned to British cities, but the eccentric Libyan ruler, Col. Muammar Qaddafi, denies he is to blame. Four years ago a spate of bombings and shootings in European cities followed a call by Colonel Qaddafi to Libyan exiles to return home or face ''liquidation.'' That campaign resulted in two murders in Britain.
This time, bombs placed in shops and restaurants in London and Manchester have injured 24 people. They have also produced a stern diplomatic reaction from the British government.
Diplomats at Libya's ''people's bureau'' (actually an embassy) in London were summoned to the Foreign Office twice in two days and warned that the terror campaign, evidently directed at anti-Qaddafi exiles, must cease.
The bureau refused to give an assurance to this effect and denied the bombs had been placed by agents working for the Libyan government.
In the past, Colonel Qaddafi is believed to have offered support to the outlawed Irish Republican Army as well as to the international assassin known as Carlos.
British police have alerted their counterparts in France and other European countries that a gang of Libyan terrorists is operating on the Continent.
There is concern that, having begun their campaign in Britain, the gang may switch its attention to other European countries.
There is also concern that Europe-based Libyan terrorists may attempt to disrupt Queen Elizabeth's tour of Jordan later this month.
The Queen is to meet King Hussein, an Arab leader whose moderate stance on Middle East issues has angered Qaddafi.
Buckingham Palace security experts have arranged for the Queen's aircraft on the trip to and from Amman to be equipped with missile-detection devices.
A detachment of special air service soldiers will guard Queen Elizabeth during her four-day state visit.
Meanwhile, the foreign secretary, Sir Geoffrey Howe, has told Britain's ambassador in Tripoli to warn Qaddafi that attempts to make political capital out of the royal visit to Jordan could lead to a complete diplomatic rupture between Britain and Libya.