Police cracked down in different areas of Lahore and detained more than 300 workers of Pakistan Tehreek-e-Insaf (PTI) before rally from Islamabad, reported 24NewsHD TV channel on Thursday.
According to police, arrests were made in view of concerns over the threat of a breach of peace.
Lists of active PTI workers were compiled and door-knocking was also done.
A record was created by collecting data on workers who escaped arrest and fled.
The locations of wanted workers are being obtained.
Cases will be registered against those who protest violently or take the law into their own hands.
Reporter: Irfan Malik