The searches began on Wednesday at Swiggy and Instakart's offices in the southern city of Bengaluru, the sources said.

The search at the office of Instakart, e-commerce giant Flipkart's logistics arm, concluded late on Thursday, one of the sources said.

At least 20 income tax officials visited the Instakart office to inspect invoices issued to its vendors, the source added.

In a statement, Flipkart said it was providing the officials with "all the required information and are extending our full co-operation", adding it was in full compliance with all tax and legal requirements.

Swiggy, backed by South African internet giant Naspers, too said it was in full compliance with tax and legal mandates.

"The survey by the IT officials is currently underway and our team is extending full cooperation in the matter."

The tax department did not immediately respond to Reuters' request for comment.

(Reporting by Chandini Monnappa and Chris Thomas in Bengaluru, Aditya Kalra in New Delhi; Editing by Subhranshu Sahu)