Bombings have killed 49 people in three different areas of Pakistan on Sunday.

In the deadliest of the attacks, twin blasts near a Shiite Muslim mosque in Quetta, the capital of southwest Baluchistan province, killed at least 28 people, including nine women and several children, said city police chief Mir Zubair Mahmood. Dozens of others were wounded.

Initial reports indicated a hand grenade caused the first blast, forcing people to run in the direction of the mosque, where a suicide bomber detonated his explosives, said another police officer, Fayaz Sumbal said.

Security forces prevented the bomber from entering the mosque or the death toll would have been higher, said the provincial Home Secretary Akbar Durrani. Radical Sunni Muslims have stepped up attacks in the past two years against minority Shiites, whom they consider to be heretics.

No-one has claimed responsibility for the attack. Suspicion will likely fall on the militant group Lashkar-e-Jhangvi, which has carried out many of the attacks against Shiites in Baluchistan in recent years.

In the northwest, a car bomb exploded as a convoy of paramilitary troops passed through the outskirts of the city of Peshawar, killing at least 17 people and wounding dozens of others, police said.

Most of the dead and wounded were civilians, although nine paramilitary Frontier Corps troops were hurt, said police official Shafiullah Khan. The blast struck one Frontier Corps vehicle, but the other passed by safely.

The explosion damaged many other vehicles and shops in the area, according to local TV video. Frontier Corps vehicles rushed to the scene, and a police officer collected evidence from the crater caused by the bomb.

Elsewhere in the northwest, a roadside bomb struck an army convoy and killed four soldiers in the North Waziristan tribal area, the main sanctuary for Taliban and al-Qaida militants in the country, said intelligence officials, speaking on condition of anonymity because they were not authorized to talk to reporters. The blast also wounded 20 soldiers, the officials said.

No-one has claimed responsibility for the attacks in the north-west but suspicion will fall on the Pakistani Taliban. The group has been waging a bloody insurgency against the government for years that has killed thousands of security personnel and civilians. The militants have proven resilient despite a series of army offensives against them in the tribal region.