The raid was conducted at 30 residential and business premises in Jaipur, Udaipur, Jodhpur, Jaisalmer, New Delhi, Sriganganagar, Haryana, Gwalior and Kolkata yesterday on suspected tax evasion.
"During the investigation, till now, Rs 5.71 crore has been seized. Some incriminating documents having details of unaccounted money have also been seized and being examined," Sanjiv, Additional Director of Income-Tax (Investigation), said.
The group is also engaged in toll collection business.
It was detected that a substantial portion of the toll collected is not recorded in the books of account and is siphoned off by the partners/directors, the I-T official said.
"The source of money utilised in this acquisition is also being investigated in this search operation," he said.
Seized documents were being examined to ascertain the quantum of undisclosed income by the group, he said, adding the search operations were still going on.