句中的over解？

A 48-year-old man has been arrested over the murder of three members of a British family and a French cyclist in the Alps in 2012.

Over 可以做 preposition (前置詞), adverb (副詞) or adjective (形容詞)
在這句子 over 是作前置詞.
Over作為前置詞, 有許多的意義

在以上這句, over 解:
Over (關于): concerning about a particular subject, person, thing or problem. It is used for saying what people disagree about or what they feel worried, sad, happy etc. about.

其他例子:
The executive officer is having problem over his income tax.

The members of the Legislative Council (立法會議員) had a row over public expenditure.

There is a concern over the bad image of the school because they hire unlicensed teachers.

There are worries over the future of the university graduates.

We spent a whole hour arguing over the meaning of two words.

Over 與 arrest 在某方面是無直接關係, 因 “arrest over” 不是 phrasal verb. “over” 使用在 prepositional phrase. "over" is followed by a noun or noun phrase to form a prepositional phrase.

“over the murder of three members of a British family and a French cyclist in the Alps in 2012” 是 prepositional phrase. 這 phrase 中有其他的 prepositional phrases 例如”in the Alps”, “in 2012”

一位48歲的男子已被逮捕過的英國家庭和法國騎自行車在阿爾卑斯山在2012年的三名成員被謀殺。

over 在這是 preposition，意思是 "with reference to"，即"鑑於"

over=arrested后面的助词
中：2012年，有一个四十四岁的男人被拘捕，因为他杀了三个英国家庭成员和一位法国单车家