Durban businessman Vivian Reddy has secured a High Court interdict stopping two controversial "economic empowerment" groups from shutting down construction sites on three projects worth more than R5.5bn.In an affidavit, which came before KwaZulu-Natal Judge President Achmat Jappie on Wednesday, Reddy's chief of staff Brian Mpono said the Federation for Radical Economic Transformation and the Delangokubona Business Forum had tried to "extort" R20m from Reddy's companies.The urgent court application was launched on Wednesday after about 200 people – said to be representatives of the two organisations – were bused into Umhlanga and effectively closed down the site where Reddy is constructing the R4bn mixed-use Oceans Umhlanga development.The business forum has been taken to court dozens of times over the past two years. In each instance members are alleged to have demanded jobs or contracts and then used violence and intimidation to shut down building sites.Mpono, in his affidavit, said the federation was a "new gang of disruptors"."But the pattern is familiar and they will disrupt until a court order is granted," he said.'We believe in black economic empowerment'The application was launched in the names of Oceans Umhlanga, Double Ring Seven Trading – which is involved in the R1.5bn KwaDukuza (formerly Stanger) Mall – and Edison Power, which is involved in electricity connections at the Dr Pixley Ka Isaka Seme Memorial Hospital, near Bridge City in KwaMashu.Mpono said all the companies had common directors.He said in early April, he had been approached by Phakama Nhassengo, who claimed to represent the forum and the federation.Nhassengo had asked about possible jobs and contracts for members."We believe in black economic empowerment. I asked for a list of services they could offer but nothing was sent," Mpono said."Then they [allegedly] sought to extort money. They said they wanted R20m otherwise they would disrupt our business. We ended the meeting," he claimed.Contractual obligationsOn April 19, a group had threatened to shut down the hospital site. "They threatened violence... so we moved off and shut down the site."On Wednesday, in Umhlanga, the large group arrived and the police, while present, seemed unable to control the crowd, he said. Mpono said the companies had contractual obligations to honour.Judge Jappie granted the interdict. The forum and the federation have until May 2 to oppose it being made final.