Britain's MI5 is tracking 30 terror plots with many having links to al-Qaeda
MI5 knows of 30 terror plots threatening the UK and is keeping 1,600 individuals under surveillance, the security service's head has said.
Dame Eliza Manningham-Buller warned the threat was "serious" and "growing".
She said future attacks could be chemical or nuclear and that many of the plots were linked to al-Qaeda.
Prime Minister Tony Blair said the terrorist threat was "very real" and spoke of "poisonous propaganda" warping the minds of young people.
MI5 has increased in size by nearly 50% since 9/11 and now stands at roughly 2,800 staff.
But according to Dame Eliza the current terror threat will "last a generation" and her concern is that even with MI5's rapid growth, the security service will not be able to investigate nearly enough of activities it deems to be suspicious.
She said hard choices would have to be made about resources.
"I wish life were like Spooks [the TV series] where everything is, a, knowable, and, b, solvable by six people," she explained.
Dame Eliza's warning comes days after a UK man was sentenced to at least 40 years in jail for planning a series of attacks.
Attacks planned by Dhiren Barot, 34, from London, included using a so-called "dirty bomb" using radioactive material.
Mr Blair also said he agreed with Dame Eliza's comments that the terrorist threat would last for a generation.
"I've been saying, as you know, for several years that this terrorist threat is very real, it's been building up over a long period of time.
"It's not just in this country, as we've seen recently from incidents in India, France, other parts of the world. This is a threat that has grown up over a generation."
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