Nine men were jailed in London Thursday on terror charges , four of them over `` an al Qaeda-inspired plot '' to bomb the London Stock Exchange , UK police said . Abdul Malik Miah , Gurukanth Desai , Shah Mohammed Lutfar Rahman and Mohammed Moksudur Rahman Chowdhury had pleaded guilty last week to the London Stock Exchange plot , police said . Five others , Abdul Bosher Mohammed Shahjahan , Mohibur Rahman , Nazam Hussain , Omar Sharif Latif and Usman Khan , also admitted terror offenses , police said . All nine were sentenced at Woolwich Crown Court Thursday to terms ranging from five to nearly 17 years , with some given indeterminate sentences with at least eight years to serve . Deputy Assistant Commissioner Stuart Osborne , the senior national coordinator for counterterrorism , issued a statement saying : `` This was one of the most significant and complex counter terrorism operations of recent years . `` We had a network of highly dangerous men based in three cities who were working together to plan terrorist attacks in the UK . `` Had we not taken action to disrupt this network , their actions could have resulted in serious casualties or fatalities . '' Miah , who had previous convictions , was sentenced to 16 years and 10 months in jail , while Desai was jailed for 12 years , and Latif for 10 years and four months . Shahjahan , Khan and Hussain were each handed an indeterminate sentence , with a minimum of eight years to serve . Mohibur Rahman was jailed for five years . Chowdhury was sentenced to 13 years and eight months , and Shah Rahman to 12 years . Osborne said a major covert operation had been put in place to monitor the suspects , who were based in London and Stoke-on-Trent in England and Cardiff in Wales . At the height of the operation , over the 2010 Christmas period , nearly 1,000 police officers and staff were involved , he said in an online statement posted by West Midlands Police . `` These men were arrested when the balance between public safety and gathering evidence meant that we could not run the operation longer , '' Osborne said . `` This plot clearly demonstrates that there are still people living in our communities who are intent on doing us harm . If we are to find them and we are to stop them we must all remain vigilant and aware . '' The investigation , which was coordinated by the West Midlands Counter Terrorism Unit , also involved police forces in London , Wales and Staffordshire , and national counterterrorism and security services .
three men are jailed in Staffordshire after admitting a string of terror offenses . `` Their actions could have resulted in serious casualties or fatalities , '' an official says . The men were based in Nine cities : London , Cardiff and Cardiff . They were arrested after a huge covert operation in four months , police said .