New Delhi, Jun 8 (IANS): Intelligence agencies are working to trace the origin of a letter reportedly written by the Al-Qaeda in Indian Subcontinent (AQIS), in which the terror outfit warned of carrying out 'suicide bombings' in the metro cities to avenge the 'insulting' remarks against Prophet Muhammad made by two now suspended BJP spokespersons.

The agencies suspect that the terror outfit might provoke the youth to join its anti-India agenda on this pretext.

This letter was circulated on social media on Tuesday. This is not the first time that the terror outfit has issued such threatening letter, but this time the security agencies are taking the matter more seriously.

Sources said that all the inputs received by the various intelligence units are being collected to prepare a comprehensive report to avoid any terror strike.

"The saffron terrorists should now await their end in Delhi, Bombay, UP and Gujarat. They should find refuge neither in their homes nor in their fortified army cantonments," the AQIS letter read.

It said the "hearts of Muslims all over the world are bleeding" and are filled with "feelings of revenge and retribution".

"At the same time, we bring tidings of death and destruction to the rulers of India, of executions and hangings, of imprisonment and being bound with chains," read the letter.

Several Muslim nations, including Afghanistan, Pakistan, Saudi Arabia, the UAE, Qatar, Kuwait, Bahrain, Indonesia and Iran, as well as the Organization of Islamic Cooperation (OIC), have officially expressed their displeasure over the remarks against Prophet Muhammad.

"The terror outfits are highly radicalised groups. They might be provoking the youth to join their anti-India campaign. The agencies are working on a number of inputs. Nupur Sharma and Nanveen Kumar Jindal are just a pretext for them to radicalise the youth in the name of jehad," said a source.