Initial reports said the blast was the result of a scuffle at the door of the crowded cafe in the village of Idvor.
B92 said a police spokesman in Pancevo told reporters the wounded were taken to nearby hospitals with unspecified injuries.
The motive for the attack was unclear Sunday; however, Radio Television of Serbia said the trouble apparently began when four people from another village were blocked at the door by security staff. The person who pulled the pin on the grenade was killed along with his brother, who had reportedly tried to stop him.
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