Bakgrunnen for at britiske myndigheter hevet sikkerhetsnivået på flyplasser fra «substansiell» til «alvorlig», var indikasjoner på at terrorister ville kapre et indisk fly og fly det inn i bygninger i London.
MI5 was told by the Indian authorities early last week about a suspected plot by militants linked to Al-Qaeda in Pakistan to hijack an Air India or Indian Airlines flight from Mumbai or Delhi.
The warning, which came after the capture of a suspected Islamic leader, was contained in a detailed «threat assessment» sent to MI5 by the Indian Intelligence Bureau. It did not state that Britain was a specific target. But police security sources said it had raised fears in London that a British city might be attacked.
The threat to hijack an Indian aircraft was uncovered during the interrogation of Amjad Khwaja, a member of a militant Islamist group involved in numerous attacks against India.
He was arrested in the southern city of Chennai earlier this month. He is said to be a leader of Harkat-ul-Jihad-al-Islami, a militant group involved in terrorist attacks in India.
On a visit to India last week, the US defence secretary Robert Gates warned that a syndicate of terror groups was hoping to foment a new war between India and Pakistan.
Storbritannia har vært på «alvorlig-trussel»-nivå siden London-bombene i 2005. Nivået ble først senket i juli ifor, dvs. for et drøyt halvt år siden.
Uttalelsen fra Gates om at terrorist-syndikat forsøker å utløse krig mellom India og Pakistan er det all mulig grunn til å ta alvorlig.