A series of explosions has hit the Iraqi capital, Baghdad, killing at least four people and injuring 13, say police. Officials said all the deaths were caused by two roadside bombs in Halawi district, while a car bomb also went off in the eastern Karrada district. Such attacks remain common in Iraq despite an overall fall in violence. The blasts come amid fears of rising sectarian tensions as the unity government faces internal divisions. The interior ministry told the BBC there had also been blasts in the Bab al-Moadam district in the north of the city, injuring three people. One woman said her child was covered in glass when the blasts shattered the windows on her apartment. \"She is now scared in the next room. All countries are stable. Why don\'t we have security and stability?,\" said Um Hanin. It was not immediately clear who was behind the attacks. Iraq\'s year-old power-sharing government is in turmoil after an arrest warrant was issued for Sunni Vice-President Tariq al-Hashemi on terror charges. The entire al-Iraqiyya group, the main Sunni bloc in parliament, is boycotting the assembly in protest. It accuses Iraqi Prime Minister Nouri Maliki, a Shia, of monopolising power. Mr Hashemi denies the charges. He is currently in Irbil in Iraqi Kurdistan, under the protection of the regional government, but Mr Maliki has demanded that they give him up.