Bank staff have been told to maintain utmost secrecy about the nature of transactions being transacted today.

They need to be especially vigilant against attempts by 'unauthorised persons to extract information' on the quantum of unaccounted money that gets reported, if at all, at branches during the course of the day.

Branches in Kerala opened to business after a break yesterday even as AMT machines continued to remain shut.

Long queues had been formed from as early as 5 am this morning as people desperately wanted to exchange legacy Rs 500 and Rs 1,000 notes with those of lesser denomination.

Not all branches, however, have managed to stock up the new Rs 2,000 and Rs 500 notes. They are currently dispensing the Rs 100 notes 'till supplies last,' a branch manager said.

Most banks, possibly except cooperative banks, have set up special counters to deal with the rush of customers on what is turning out to be a long working day.

Banks are open until 6 pm today and will do business also on Saturday, a second Saturday which is normally a holiday, and on Sunday.

Some banks have issued advance circulars asking staff not to seek leave at least for 'some time in the short term.'

Meanwhile, police security had been requisitioned at some places in view of the milling crowds in front of bank branches.