Image copyright AFP Image caption The blast in Parachinar is the third this year

Scores of people have been killed and many injured in bombings, protest marches and shootings in the north and south of Pakistan, officials say.

At least 25 people were killed in two explosions at a market in the north-western town of Parachinar.

The local MP told the BBC four more people died later when security forces confronted an angry crowd protesting about the poor security situation.

Earlier at least 13 people died in a suicide bombing in Quetta.

Violence also hit the city of Karachi, where at least four policemen were reported to have been shot and killed on Friday evening.

Image copyright AFP

Police say the two explosions in Parachinar went off almost simultaneously near a bus terminal at the market. The second blast happened as rescuers rushed to help those injured in the first explosion.

The bombs in Parachinar, in Kurram district, were the third attack since January and took place as the market was crowded with people buying food to break their Ramadan fast.

Some reports say a Shia procession was targeted - the Kurram region has a history of sectarian violence between Shia and Sunni Muslims.

Most people in Parachinar are from Pakistan's Shia minority.

Sunni hardliners, currently operating through different factions including the Taliban and so-called Islamic State (IS) consider Shias to be heretics and worthy of death.

These groups have sanctuaries in Afghan and Pakistani areas surrounding Kurram, and have launched frequent attacks against civilians in Parachinar.

Earlier on Friday a suicide car bomber in the city of Quetta killed at least 13 people. It happened when the vehicle was stopped by police at a checkpoint.

Two different militant groups claim they carried out that blast, which reverberated across the city, breaking windows of buildings in the area.

Image copyright EPA Image caption Debris from the Quetta blast was scattered across a wide area

Image copyright AFP Image caption Funerals for many of those killed in the Quetta blast took place later on Friday

There has so far been no explanation as to why two militant groups - IS and an offshoot of the Taliban called the Jamaat-ul-Ahrar - have both said they carried out the attack.

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Eyewitnesses said many of those killed were police - the bomb was detonated close to the office of the inspector general (IG) of police - but it is possible the assailants were trying to enter the nearby army cantonment.

Bomb disposal officials say the car was carrying up to 95kg (210lb) of explosives.

Image copyright AFP Image caption Smoke from the blasts in Parachinar could be seen billowing above the city

TV pictures at the scene of the blast showed debris scattered across a wide area as security officials secured the site.

Quetta is about 100 km (60 miles) east of the border with Afghanistan.

The province of Balochistan and its provincial capital Quetta are among the most dangerous parts of Pakistan, continually targeted by militants and also by Baloch nationalist separatists waging a long-running insurgency.