Police in the Pakistani city of Karachi have used tear-gas to disperse hundreds of supporters of an ethnic political party, the MQM, who were protesting against a government decision to ban political rallies.

Earlier, the authorities in Karachi said they were planning to arrest about seven-hundred people for crimes of violence following the imposition of central government rule.

The provincial governor of Sindh Moinuddin Haider, said two hundred were wanted for terrorist offences and the others for robbery, car theft and extortion.

But he said the Pakistani government was keen to avoid the excesses of previous security sweeps in the city.