PORTLAND, Ore. (AP) — Two signs claiming that Jewish people were responsible for 9/11 were found hanging over an Oregon highway this past weekend.

The Oregonian/OregonLive reports the signs were found Sunday by a passer-by. Michael Orrantia saw the signs hanging from both sides of a pedestrian crossing above the highway.

Sgt. Pete Simpson, spokesman for the Portland Police Bureau, confirmed that police did field a call about the signs but they referred the case to the Oregon Department of Transportation.

Department spokesman Don Hamilton says by the time his agency heard about the signs, they were gone. Both Simpson and Hamilton speculated that the signs may have been removed by a citizen.