Groups Google : Terrorism Strictly Forbidden in Islam Fatwa
Islamic teachings say that it is better to leave 99 sinful people than to kill one innocent person, and as the Holy Qur’an says "whosoever kills a human being for other than manslaughter or corruption in the earth, it shall be as if he had killed all mankind [Surat al-Maeda; Verse 32]." This verse reveals two things, killing of a person is a sin, it is strictly forbidden [haram], and considering this killing lawful, this is blasphemy. Whenever a suicide bomber carries out an operation that results in the death of innocent people then this is prohibited and totally haram.
Terrorists brainwash the youth, until they carry out suicide bombings believing that this is jihad. They are the Khwarji of today, according to the hadith the Khwarji "are the dogs of hellfire" because they diverge from the true path and bring division amongst the Muslim community. They believe that this is a kind of jihad and that they will go to heaven, but they will not go to heaven. These young suicide bombers have been brainwashed, they believe they will become heroes of the ummah, but this is not true at all, they will become heroes of hell, and they will be commemorated there. They are not going to heaven, they are going to hellfire.
There are three kinds of people that you can consider to be on the extremist terrorist side.
1) Firstly there are the extremist leaders.
2) The second category are those who are 100 percent brainwashed; they have no ability to understand, they are not open to reason, or they are in a situation where no book can reach them.
3) Excluding these above two categories of people, next are the thousands of youth who have not yet reached this point, but who are already proceeding along this path, and they have the potential to become extremists and terrorists. These youths number in the thousands, they are much larger in number [than the previous two categories]. They can be described categorically, and according to Sheikh al-Islam Ibn Tammiyah, who said that they were the "Khwarij of today." The Holy Prophet said that they will continue to emerge in my ummah throughout history, their presence is continuous, and the last of them will emerge with the Masih ad-Dajjal [false Messiah, Anti Christ]. They are not going to heaven, they are going to hellfire.