Turkish police have detained a total of 17 people as part of an investigation regarding Turkish-Iranian gold trader Reza Zarrab, state-run Anadolu news agency said on Tuesday. Zarrab is cooperating with prosecutors in a US trial. No details were available on the probe regarding Zarrab, who has pleaded guilty to charges that he schemed to evade US sanctions on Iran, Reuters said. The trader is also reportedly testifying for US prosecutors against a Turkish banker facing related charges.