Accident casus just in the middle of investigating further.

事故原因正在进一步调查之中。

youdao

Religion is seldom the casus belli: indeed, in many struggles, notably the Middle East in modern times, it is amazing how long it took for religion to become a big part of the argument.

宗教信仰很少成为开战的理由：实际上，令人惊奇的是在很多斗争中，特别是在现代的中东，宗教信仰成为争论的焦点需要多少时间。

youdao

And to many it is a powerful casus belli to which a head of government has now lent credence.

ECONOMIST: Mahathir Mohamad

But George Bush and Tony Blair will no doubt be hoping that the casus for their victorious belli turns up soon.

ECONOMIST: The conflict is over. Now for the casus belli

The closest thing to a casus belli in Britain's drug war is a schedule of banned substances drawn up in the early 1970s.

ECONOMIST: Illicit drugs