Officials said the department sleuths got a tipoff that an apartment in the Yeshwanthpur locality had some cash but they could not execute the search yesterday as the old lady living in the flat refused to cooperate with the taxman and tie the two canines she had.
Finally, the sleuths made an entry with the help of locals and police and found a room that was locked.
It was also noticed by the I-T teams that a person visited the flat in the wee hours.
"The locked room was opened and unexplained cash to the tune of Rs 2.89 crore, which includes Rs 2.25 crore of new Rs 2,000 notes, was found.
"Entire cash has been seized and further investigation is in progress in this case," the department said in a statement.
In a separate case in Goa's capital Panaji, the department seized Rs 67.98 lakh in new notes of Rs 2,000 from a person who met the sleuths who were acting as decoy customers in desperate need of cash.
"The seizure was made from a place called Banda on the Maharashtra-Goa border," they said.
The department's probe wings of Karnataka and Goa, post demonetisation, have seized a total of Rs 29.86 crore, with Rs 20.22 crore in new notes, 41.6 kg bullion and 14 kg jewellery as part of investigative action to check profiteering in the wake of currency ban.
The department said it has detected unaccounted income worth Rs 1,000 crore as part of 36 operations launched till now by it in these two states.