Can a word function as a relative adverb and a relative pronoun simultaneously?

For example in a sentence like “This is the place where he was murdered”, is where functioning as both a relative adverb and a relative pronoun?

Here where acts as pronoun as it refers back to its antecedent and also as relative adverb (according to Wren and Martin) but what i want to know is

1. Do they always work in this way?

2. A lot of places I have seen that simply say that the word where modifies noun, a lot of grammar books say but How? Like it isn’t adding something to the meaning of verb (was assaulted). Instead of telling me that this is a relative adverb I want an explanation or is it something that just needs to be classified as what renowned grammarians have classified because I haven’t quite come up with any reason that proves it. One reason I could come up with was that where modifies the verb by relating a clause (this is the place) with it.