Cape Town – The senior police commander investigating former Western Cape police commissioner Arno Lamoer told the Western Cape High Court on Tuesday of the challenges he encountered when probing colleagues for corruption.Fears of witness tampering and disappearing evidence were some of the difficulties Colonel Abdul Enus, the commander of the corruption unit of the Directorate for Priority Crime Investigation, the Hawks, pointed out in his testimony.It relates to the corruption case against Lamoer, tow truck company owner Salim Dawjee, and Brigadiers Darius van der Ross, Sharon Govender and her husband Colin Govender.The accused face 109 charges. They have pleaded not guilty to accepting money from Dawjee in exchange for favours.A trial-within-a-trialThe court is holding a trial-within-a-trial to determine whether an application to conduct surveillance of the accused was procedurally correct.Enus was questioned about why the investigation took so long."Detectives were being intimidated," he told the court, before adding that “people willing to make statements were sitting right next to my suspect”.Enus added that there were regular trips from "national" to get certain individuals suspended so that the investigation could take off."Premature exposure of this investigation could have led to some of our people removing things...things disappearing," he said.The court heard that he could not even go to the Cape Town police station for enquiries because one of the people he regarded as a suspect worked there. He did not want the investigation to be exposed.Long waitDawjee's counsel William King SC, wanted to know why Enus had waited so long to make his move on the accused, despite tip-offs received and information handed to him since 2013.One of the tip-offs was that Dawjee allegedly approached a gun shop in Parow to have a firearm refurbished, which police had confiscated from a woman during a raid.She had allegedly told officers who were raiding her home for drugs that they would find her late husband's unlicensed firearm in her safe. She said she did not know what to do with it after his death and kept it locked up.Police confiscated the firearm, but it allegedly ended up in Dawjee's possession. A document recording its handing in had been marked "case withdrawn".Enus said he had been sent to a gun shop in Parow to chat to the owner at the request of a colleague.Apparently, the gun shop owner relayed that Dawjee had wanted ammunition and to have the gun cleaned up, even though he did not possess a valid licence.Investigation diary stolenThe court also heard that Enus's investigation diary was stolen from him and he had to reconstruct details of his investigation from case files and other sources.During his testimony, Enus had to recall several dates relating to the investigation and conversations that he had had.By the end of the day, after having numerous questions fired at him, the colonel appeared worn out.The trial-within-a-trial continues on Wednesday.