After a suicide bomber blew herself up Saturday on a bus taking students to a university in the southwestern Pakistan city of Quetta, between 23 and 28 people more people, including four militants, died during the subsequent siege at the hospital where many of the survivors were taken, CNN reported Sunday.

Pakistan's Interior Ministry said at least 14 women were killed in the bus explosion, and 20 people were wounded. A police official in Quetta told CNN all the victims were women teachers and students. Officials said they did not think any foreign actors were involved.

An extremist Sunni Muslim militant group, Laskar-e-Jhangvi, claimed responsibility for both attacks and told the BBC they were revenge for a raid carried out by Pakistani security forces against the group. Al-Jazeera reported that Quetta's deputy commissioner, Abdul Mansoor Khan, was among those killed on Saturday, along with four nurses at the hospital. 

Baluchistan, the province of Pakistan where Quetta is located, borders Afghanistan and Iran and is perhaps the most volatile in the country. Al-Jazeera reported that another town in Baluchistan suffered a rocket attack that killed a policeman, and since the beginning of the year, more than 300 people have been killed in sectarian violence.


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