The death toll in four days of ethnic violence in Pakistan's southern port city of Karachi rose to 61 as 10 more people died Friday, rescue workers said, according to dpa. The fighting broke out Tuesday between the Urdu-speaking majority and the Pashtu-speaking minority when an important Pashtun leader was assassinated. The rival groups exchanged fire in the streets, and stray bullets also hit bystanders, killing some women and children. Gunmen on motorcycles fired at pedestrians and buses. Ten people died Friday and 10 more were injured while 24 died and 49 were injured Thursday, said Faraz Ali, a spokesman for the private Edhi ambulance service. "According to our records, 61 people have been killed in four days of violence and 136 injured," he said. The Urdu-speaking Muttahida Qaumi Movement (MQM) and the Pashtu Awami National Party are competing for political influence in Karachi, a city which has a population of more than 18 million and is the financial hub of Pakistan. The two groups have a three-decade history of clashes, during which hundreds of people have died. The MQM was observing a day of mourning Friday with most of the business centres and educational institutions closed in the city. Public transport was reduced. Interior Minister Rehman Malik said the federal government was sending in 1,000 additional paramilitary troops to curb the violence.