The Czech tennis player suffered a left hand injury.
Knifeman stalks victim while concealing blade behind his back.
A 34-year-old man is in a serious condition while two suspects remain on the run, according to local media.
Two girls are also in serious condition after Saturday’s attack.
ZURICH, Aug 13 (Reuters) - Six people were injured in an attack aboard a Swiss train on Saturday by a man armed with a knife
More information emerges on the man believed to have killed 19 people at a center for the disabled.
Police said they are investigating whether there was an Islamist motive to the attack.