letter bomb

音标发音

To this, the explanation of concerned staff of farming letter agency is: They are having imitate practice, these smother are to put tear bomb on be caused by artificially.
对此，农信社有关人员的解释是：他们在进行模拟演习，这些浓烟是人为投放催泪弹所致。
On September 19th 1972 a letter-bomb in London killed Ami Shachori, an Israeli diplomat. Almost all the 51 similar bombs posted to Israeli embassy employees around the world were intercepted.
在伦敦，1972年9月19日，一名以色列外交官Ami Shachori死于信封炸弹，另有约51枚列斯炸弹寄往世界各地的以色列大使馆工作人员，几乎全部被截获。

Mr Zilk, whose hand was damaged by a letter bomb sent by Austrian neo-fascists five years ago, said the charge was absolutely groundless.
ECONOMIST: Czech Republic
In 2011, a Danish court sentenced a Chechen-born man to 12 years in prison for preparing a letter bomb that exploded as he was assembling it in a Copenhagen hotel.
NPR: Russia's Chechnya Has Seen Decades Of War, Terror
On September 19th 1972 a letter-bomb in London killed Ami Shachori, an Israeli diplomat.
ECONOMIST: A history of parcel bombs

A letter bomb is a small bomb which is disguised as a letter or package and sent to someone through the mail. It is designed to explode when it is opened.