Security checks were stepped up at Swiss airports and at the borders amid nervousness following the Brussels attacks.
There was a high presence of armed cantonal police at Zurich airport on Tuesday, the Tages-Anzeiger reported.
Several dozen police officers were checking passengers in the arrivals and departure halls of Switzerland’s biggest airport.
However, the Federal Office of Civil Aviation, which has the power to order a higher level of security at Swiss airports in view of a heightened threat had not done so, the paper said.
The Swiss Border Guard had also stepped up its checks in international trains and at border points, a spokesman told the paper.
The Federal Intelligence Service said on Tuesday it had no evidence of a specific threat to Switzerland.
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