The ED had received "specific inputs" that these entities were involved in unauthorised receipt of foreign remittance through payment gateways in the name of providing e-visa services to foreigners, it said.
The agency said the preliminary probe found "two such entities received foreign remittance of more than Rs 200 crore for processing Indian e-visa applications of foreigners without any authorisation from the government."
"These entities were also involved in high value suspicious transactions," it said.
It was also found that "certain chartered accountants played a key role in managing the affairs of these entities and were behind the suspicious transactions carried out by them."
"The seizure of unaccounted cash during the raids has raised further suspicion about the operations of such entities and blatant violation of statutory requirements," the ED said.
A probe is underway and the directors and executives of these firms will be questioned, a senior agency official said.