At least 50 people were killed and more than 100 wounded in a string of attacks Sunday across Pakistan, news agencies quoted officials as saying. The deadliest incident was a suicide bombing of a Shiite mosque in south-western Quetta city, killing 28. Around 70 people were injured in the assault, which came a fortnight after multiple attacks killed 30 in the city including female university students, said Khan Wasseh, spokesman for the paramilitary Frontier Constabulary (FC). It is believed a suicide bomber disguised as a woman detonated explosives he was wearing at the main entrance of the mosque in the Hazara Town area of Quetta, a police official said. Minutes later, another blast hit a shopping centre in the same locality, Khan Wasseh said. Also Sunday, suspected militants attacked two convoys of security forces at separate points in north-western Pakistan, killing 22 people and injuring 56, officials said. Four troops, two children and one woman were among the dead in bombings just hours apart, police and military officials said. In the first incident, a car bomb targeting paramilitary troops on patrol just outside Peshawar killed 18 civilians and injured 46 people, police official Shafiullah Khan said. In a separate attack, four army soldiers were killed when their vehicle hit a roadside bomb in the North Waziristan tribal district near the Afghan border, military officials said. At least 10 troops were wounded in that incident, a statement by the military's media wing said. Four troops from the Frontier Corps were among those wounded in the blast in Peshawar, capital of the volatile Khyber-Pakhtunkhwa province, Shafiullah said. Two of the three vehicles, carrying around two dozen troops, passed through the area safely. However, the third was hit by mortar shells fitted in a car parked at a fuel station, the police official said. The attack used at least 40 kilograms of explosives, said bomb disposal squad official Abdul Haq, who was at the scene to gather forensic evidence for investigation. The blast damaged four shops and a dozen vehicles, police official Abidur Rehman said. No group claimed responsibility for any of the attacks.