Prime Minister Imran Khan has taken notice of the roadblocks erected by authorities to regulate rallies held by opposition parties across the country to observe 'black day' on July 25, Minister for Science and Technology Fawad Chaudhry announced on Friday.

In a tweet, the minister said the prime minister had directed authorities that the opposition "should be free to hold peaceful rallies and protests".

Allowing them to hold public gatherings freely "will only expose the Opposition as they hold no street power and people of Pakistan are sick of them", the minister quoted the premier as saying.

To mark the one-year anniversary of the 2018 general election that they believed had been rigged to bring the Pakistan Tehreek-i-Insaf into power, opposition parties had on Thursday observed 'Youm-i-Siah' by holding public gatherings in the four provincial capitals.

Lahore witnessed an impressive show of power by the opposition parties on the Mall Road, though the Punjab government had denied permission for the event. Police placed barricades and blocked all thoroughfares leading to the protest venue. PML-N leaders said the police had blocked rallies on Ring Road and Shahdara.

The opposition workers had occasional brawls with police while forcing their way to the Mall Road. However, no injury was reported.

PkMAP Islamabad president Abdul Qayyum Achakzai, who addressed a rally in Islamabad, claimed that supporters of his party were unable to join the opposition rally in Balochistan because roads across the province had allegedly been blocked.

Activists and sympathisers of major opposition parties took out processions in different parts of the country, particularly in Sindh.

Speaking at different public meetings, the leadership of the main opposition parties — the PML-N and PPP — termed the 'black day' the beginning of the end of the PTI government.

The opposition leaders vowed to continue their struggle to seek mid-term elections in the country at the earliest to “restore democracy in a real sense and get rid of inefficient rulers”.