A device containing about 5lb of explosive was left in Brighton and one with about half that amount in Bognor Regis, police said yesterday. Both were hidden in panniers on the back of blue mountain bicycles.
The device in Brighton, East Sussex, was left in a busy area used by tourists. The bicycle, locked to railings next to a cast-iron lamp post near the Palace Pier, was found and dealt with in a controlled explosion on Saturday night.
Earlier, the device left at Bognor Regis, West Sussex, had exploded, shattering shop windows.
Richard Childs, Assistant Chief Constable of Sussex, said yesterday that information indicated there was a timing mechanism in the Brighton bomb which appeared to have contained Semtex explosive.
He said: 'Leaving the device in this position could have had devastating consequences.'
Police renewed their appeals for information about the bicycles and for any video footage or photographs taken by tourists in Brighton and Bognor Regis on Saturday.
As they checked security videos from shops in Bognor Regis town centre, police also appealed for help from firms hiring out bicycles.
The attacks, accompanied by warning telephone calls which gave no precise locations, came exactly a year after a series of IRA firebombs went off in the resort of Bournemouth, Dorset.
The Bognor Regis bicycle was left locked to a cycle rack outside Woolworth's. A Townsend Oregon mountain bicycle, it had the numbers 20-2 written in white Tippex fluid on the part of the frame leading from the handlebars to the front forks. On the D- lock securing it the number 26 was written in the same type of fluid.
After a warning that a device had been left in Brighton, police closed the Palace Pier and found the second bicycle, a French-made Gitane Bullet, again secured to railings using a D-lock on which the number 16 was written.