Jamaat-e-Islami leader Hafiz Naeemur Rehman has cried foul in the bypolls.
"Election rigging also has limits.The police, along with a political party, attacked our workers," he said while talking to the media at the Jinnah Hospital.
A worker was hit on the head with a brick, he said questioning if the election was battle of ballot or battlefield.
Legal action will be taken against the accused, he added.