While two locations were raided at Rourkela in Sundargarh district, raids were conducted at several places including Barbil in Keonjhar district, the police said.
Raides were carried out simultaneously at the office and residential premises of a transporter and one railway employee at Rourkela as part of the CBI's investigation, the police said.
However, it was immediately not clear whether the sleuths seized any document and material during their raids as CBI officials were tight-lipped about the outcome of the entire operation.
Raids were also conducted at some locations in Barbil area as well as railway sidings in Keonjhar district for which separate teams had been formed, they said.
The raids were part of the probe into alleged fraud and irregularities committed by some mining companies by showing ransport of iron ore meant for exports through railways as movement for domestic consumption.
As the domestic freight charge for iron ore transportation is much lower than the rates fixed for exports, the Railway was believed to have suffered loss due to the alleged fraud, the police said.