Johannesburg - There is no excuse for assault, killings and looting of foreign-owned shops in Soweto, Cosatu said on Thursday."The police must take action, but in an even-handed way, treating all people equally," the Cosatu spokesperson Patrick Craven said in a statement."The problems we face - unemployment, poverty and crime - must never be blamed on people on the basis of their country of origin."The trade union federation condemned the violence. It called on the alliance, which was made up of Cosatu, the ANC and the SACP, and civil society in Gauteng, to campaign in the affected areas to help stop the violence.Police were on high alert in Soweto on Thursday, the third day of clashes between locals and foreigners that left at least two people dead.Two local teenagers have been shot dead and two injured since violence broke out between locals and foreigners in Snake Park on Monday.Nearly 70 people have been arrested on charges including murder, robbery, public violence, and illegal possession of firearms. Eight of them were foreign nationals allegedly found in possession of unlicensed firearms.One was a policeman caught on camera allegedly taking part in the looting.The looting started on Monday after 14-year-old Mthetheleli Siphiwe Mahori was shot dead, allegedly by a foreign shop owner in Snake Park. He was apparently part of a group that tried to rob the shop.On Thursday, Senosi Yusuf appeared in the Protea Magistrate's Court accused of killing Mahori. His case was postponed to 26 January for a bail application.Second teen shot deadThe Star reported on Thursday that a second teenager, Nhlanhla Monareng, 19, was shot dead when police fired into a crowd gathered at a Pakistani-owned shop on Wednesday night. He was a bystander and reportedly friends with the Pakistanis.A 74-year-old Malawian shopkeeper, Dan Mokwena, was attacked and killed as she slept in his shop in Durban Deep, Roodepoort, in the early hours of Wednesday morning, The Star reported.Four foreigners charged with possession of unlicensed firearms and ammunition appeared in court on Thursday. Their bail applications were postponed to 29 January.The Ahmed Kathrada Foundation expressed concern at the spate of attacks on foreign business owners in Soweto. It said the attacks formed a pattern similar to the 2008 xenophobic violence."We consider these attacks to be xenophobic and condemn them as such. We urge all community leaders to rally residents around the ideals upon which our Constitution and democracy is founded," the foundation said.The National Education Health and Allied Workers Union condemned the attacks and called on police and government to take action against the perpetrators.