Narrative:

VFR helicopter inbound to from northwest at 1;500 ft. Unknown target appeared off his left side approximately same altitude. I called traffic who took evasive action and descended immediately to about 1;200 ft.

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Original NASA ASRS Text

Title: Local Controller described a conflict event between a VFR helicopter arrival and an unknown target suddenly appearing to the side of the helicopter.

Narrative: VFR helicopter inbound to from northwest at 1;500 FT. Unknown target appeared off his left side approximately same altitude. I called traffic who took evasive action and descended immediately to about 1;200 FT.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.