でいる

[Elizabeth]

走り去る姿でいる is semantically odd, since 走り去る expresses an action "to run away from a location", whereas 姿でいる means "to stay/exist in a location in the state of~". Those two expressions can't coexist together.

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Oh, that makes all kinds of sense. Switching around from でいる to 路地に should be fine therefore to indicate the existence of the man in the alley as well as the direction, movement or destination of his action. I really need to get back here more frequently.

腕に血のようなものを付けたまま現場の近くの路地に走り去る姿が(いるのを)目撃 されている

その話のくどさはいらいらさせたかな。。。。haha

 

[Toritoribe]

Again, 走り去る姿がいるのを doesn't make sense. 路地に has nothing to do with this.

そうですね。いい加減辟易してきてます。間違いはいく ら言い繕っても間違いです。過ちを改むるに如くはなし 、ですよ。

 

[Elizabeth]

Again, 走り去る姿がいるのを doesn't make sense. 路地に has nothing to do with this.

そうですね。いい加減辟易してきてます。間違いはいくら言い繕っても間違いです。過ちを改むるに如くはなし、ですよ。

That is strange. Another Japanese friend told me it was not a mistake, although of course the normal phrasing would be
腕に血のようなものを付けたまま現場の近くの路地に走り去る姿が目撃 されている. Sorry for your troubles !

 

[Toritoribe]

Ask him/her again. 走り去る姿がいるのを目撃されている no doubt sounds strange.