Two attacks in Quetta, which saw at least 24 people killed, has sent Pakistan into a state of grief and shock and raised fears of renewed tension in Balochistan's capital city.

National newspapers on Sunday carried headlines decrying the two deadly blasts, the first of which happened on a bus near the campus of the Sardar Bahadur Khan Women's University with a bomb hidden in the vehicle, killing at least 14 female students.

The second blast struck the casualty ward of the Bolan Medical Complex, where the wounded were taken, and a gun-battle continued in the aftermath. At least eight unidentified gunmen were reported to have taken positions in the hospital, and killed at least four security personnel who were attempting to resecure the facility and four nurses, local officials said.

Quetta's Deputy Commissioner, Abdul Mansoor Khan, was also among those killed on Saturday.

The banned Lashkar-i-Jhangvi, which has links with al-Qaeda, has claimed responsibility for the attacks. Reports said a female suicide bomber carried out the first attack.

"Killing hope and history," The Express Tribune said, "14 girls, deputy commissioner among 25 killed," said Dawn.

"Across the country, there is shock as well as grief," said Al Jazeera's Kamal Hyder, reporting from Islamabad.

Three-day mourning

Chaudhry Nisar Ali Khan, the country's interior minister, said the hospital siege and ended with security forces freeing 35 people trapped inside the building and killing four of the attackers. One of the attackers was also arrested.

Zubair Mahmood, the city police chief, said the bomb on the bus exploded after students had boarded and the bus was leaving the university, which is the only school solely for women in the province.

Another police official, Fayyaz Sumbal, added that the bus caught fire after the explosion and many students were critically wounded.

"As casualties were being brought to the hospital, terrorists had taken position inside the hospital building," Khan told reporters. "They opened fire on on administration and police officials who arrived at the hospital. One suicide bomber blew himself up in the hospital."

Pakistani security forces surrounded the hospital and carried out an operation to clear it once the gunmen had taken over.

“Four female nurses were killed in firing,” said Riaz Louise, the President of Balochistan Nursing Federation, announcing a three-day mourning, according to the Dawn newspaper.

Quetta is the capital city of Balochistan province, and regularly witnesses violence on a large scale.

Earlier on Saturday in the town of Ziarat - some 120km from Quetta - a rocket attack by unknown attackers killed a policeman and gutted a historic summer retreat used by Pakistan's founder Muhammad Ali Jinnah.

Since the start of the year, more than 300 people have been killed in attacks by sectarian, ethnic and anti-state groups in Quetta.