The advisory was issued after PTI Chairman Khan was taken into custody outside the Islamabad High Court (IHC) by Rangers officers acting under a warrant from the National Accountability Bureau (NAB).
Following his arrest, the PTI asked its followers to demonstrate and "block all roads, close all shops" in the country.
The PTI workers staged demonstrations in a number of cities, including Islamabad, Rawalpindi, Lahore, Karachi, Gujranwala, Faisalabad, Multan, Peshawar, and Mardan.
Near the nursery in Karachi, protesters and police engaged in physical conflict. They wrecked a bus, tore down street lights, and set fire to police cars while hurling stones at them. According to reports, police shot tear gas rounds at the demonstrators.
Other cities where protests took place also saw public property damaged, including Rawalpindi and Lahore.
Exercise a high level of vigilance in Pakistan due to the uncertain security scenario, the Canadian delegation advised in response to the country's deteriorating law and order situation. Terrorism, civil upheaval, sectarian bloodshed, and kidnapping are all threats, the advisory read.
Additionally, the Canadian consulate warned citizens against visiting Karachi because of "violence and the risk of terrorism."
Due to the recent arrest of the PTI chief, protests are anticipated to occur across Pakistan, according to the high commission.
It added that the security situation in Pakistan "is evolving and remains unpredictable" and highlighted that the security forces are on high alert in Islamabad, Rawalpindi, Lahore, and Karachi.
"Follow the instructions of local authorities; avoid areas where demonstrations and large gatherings are taking place; always be aware of your surroundings when in public places; monitor local media for the latest on the situation," the Canadian mission advised its citizens.
On the other hand, the US Embassy in Pakistan canceled its consular appointments today and said it was keeping an eye on rumors of clashes in Islamabad and other places.
"Exercise heightened vigilance and avoid locations with large crowds," the US mission urged its nationals. Along with carrying identification with them and adhering to police requests, it advised its citizens to "review" their "personal security plans".
The United Kingdom likewise upgraded its travel advisory for Pakistan a day early.
Acting British High Commissioner Andrew Dalgleish posted the news on his Twitter account.
The travel advice, which was titled "updated information on political rallies and protests," advised British nationals against visiting particular locations.