偶発(ぐうはつ)sudden outbreak, accidental, incidental

事件(じけん)が偶発(ぐうはつ)してしまいました。

The incident accidentally occurred. {sudden outbreak, accidental, incidental}

偶発(ぐうはつ)した脱線(だっせん)事故(じこ)の原因(げんいん)を解明(かいめい)する。

Clarify the cause of the accidental derailment incident. {sudden outbreak, accidental, incidental}

偶発(ぐうはつ)的(てき)に起(お)きた事故(じこ)の責任(せきにん)者(しゃ)は誰(だれ)なのでしょうか？

Who is responsible for the accident that happened incidentally? {sudden outbreak, accidental, incidental}

その事故(じこ)は偶発(ぐうはつ)的(てき)なのだろうか？それとも誰(だれ)かが意図(いと)したものだろうか？

Was that incident accidental? Or was it something someone intended? {sudden outbreak, accidental, incidental}

事件(じけん)が偶発(ぐうはつ)するなり、通報(つうほう)を受(う)けた警察官(けいさつかん)たちがパトカーで現場(げんば)に向(む)かいました。

As soon as the incident accidentally occurred, the police officers who received the report headed to the scene in their patrol cars. {sudden outbreak, accidental, incidental}