That appears to be what the Koran says on the matter.
Holy Koran wrote: Within most of Islam, hostage taking, suicide, or terrorist attacks are not permitted. They are considered a great sin. In the Qur'an, it is written that "If anyone killed a person, unless it was for murder or spreading mischief on earth, it would be as if he killed all of mankind. And if anyone saved a life, it would be as if he had saved the lives of all mankind." (Qur'an 5:32)
Prior to the rise of a minority of extremist, radical, Fundamentalist Muslim clerics:
* The taking and maltreatment of hostages has not been permitted within Islam.
* Suicide has been generally forbidden in Islam.
* Muslims have been forbidden to attack innocent civilians; they have not even been permitted to kill an unarmed soldier in wartime.
http://www.religioustolerance.org/reac_ter14.htm