The rebels were responsible for the mass murder of 400 civilians.

叛乱者对屠杀400名平民负有责任。

《牛津词典》

During their brief rule there, there was a bloody reign of terror in which 3,000 civilians were clubbed, shot to death, and buried in mass graves.

在他在那下达简令的规则时，这有一个血腥的统治，三千的平民被抢棍打死，然后被全体埋葬。

youdao

Secretary Clinton is also scheduled to make a brief visit to Goma in eastern Congo, where government soldiers in North and South Kivu provinces have been accused of mass looting and raping countless civilians.

VOA: standard.2009.07.31

Linnas lost his U.S. citizenship in 1981 when the Justice Department accused him of being involved in the mass killings of civilians in Estonia during World War II.

CNN: AllPolitics - News

TUZLA, Bosnia-Herzegovina (CNN) -- Hurem Suljic carries a tale of mass murder of Muslim civilians that could tear apart Balkan peace talks.

CNN: Survivor: Mladic directed mass killing

While speaking out for human rights, some organizations cynically support terrorists bent on mass killing of civilians.

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