The security of the UK is facing a threat from a small number of hotheads who are heading to the Arab world for training and opportunities in militant activities, says MI5 Chief Jonathan Evans.
Speaking at the Lord Mayor's Annual Defence and Security Lecture, the Director General of MI5 said these would-be terrorists will return to the UK and pose a threat.
"A small number of British would-be jihadis are also making their way to Arab countries to seek training and opportunities for militant activity, as they do in Somalia and Yemen. Some will return to the UK and pose a threat here. This is a new and worrying development and could get worse as events unfold. So we will have to manage the short term risks if there is to be a longer-term reward from the Arab Spring," said the security service chief.
Evans was speaking in public after nearly two years. He said parts of the Arab world have once again become a permissive environment for the al-Qaida after gradually losing its footing in Afghanistan and Pakistan.
The group moved to Afghanistan from the Arab region in the 1990s and later to Pakistan after the fall of Taliban. Now, terrorism is heading back to its place of origin in the Arab world completing a full cycle, said Evans.
He insisted that the Afghan war for more than a decade kept terrorism under control.
The pullout of Nato troops from the region should not be the cause of resurrection of militant groups including Taliban and al-Qaida in Afghanistan, he said.
Nato will withdraw its troops from Afghanistan by the end of 2014 while some of the countries including France will carry out an early withdrawal.
Concerns are growing over recent developments in Iran. Citing Iran's craving for nuclear capability, Evans said state-sponsored terrorist activities from Iran also cannot be completely ruled out if pressure mounts on the country from the international community.
A series of terrorist attempts by Iran including the ones on Israeli interests in India, Azerbaijan and in other places are clear examples of concern, said Evans.
The MI5 chief also spoke about the astonishing growth of cyber threats in the UK. Security forces are bracing up for the London Olympics 2012, an attractive target for terrorists, he said.
For the full speech, click here.