The incident occurred in Darien on Friday, at a multi-family residence on West Avenue.
According to Sgt. Mauricio Vigil of the Darien Police, the resident told officers she found the blood-like substance in the bathroom and disturbed items after returning from work.
The residence was unoccupied with the door unlocked; however, no items were reported missing, Vigil said.
The case remains under investigation by the Darien Detective Division.
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