The ED, it is understood, wants to grill Vadra about the operations of a firm -- Ms Skylight Hospitality Private Limited -- allegedly linked to him, which had purchased land in the area.
Vadra and his mother Maureen had appeared before the ED on Tuesday.
The Rajasthan government had, in January 2015, cancelled the mutations (transfer of land) of 374.44 hectares of land, after the land department claimed to have found that the allotments were made in the names of "illegal private persons".
His mother Maureen was also questioned for some time.