Political parties are organised along ethnic or sectarian lines, and represent the city's Urdu-speakers, Sindhis, Baloch, Pashtuns and Barelvi Sunnis.

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Liaqat Baloch, secretary general of Pakistan's most popular Islamic party, Jamaat-e-Islami, said members of his party were strongly considering boycotting the elections.

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But there have also been separate battles over turf between the city's Baloch community - the original inhabitants of the city - and the MQM.

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