Chaotic scenes have been witnessed across India as millions of people wait to change old currency notes which have become worthless after the government demonetised high-value notes.

Scuffles broke out in New Delhi after ATM machines ran out of notes, as well as minor stampedes when thousands of people waiting in a queue surged forward to enter bank buildings.

Paramilitary troops posted at banks in some of the most congested areas of the city walked among the crowd, urging people to stay calm.

Earlier in the week, India's government made a surprise announcement that all 500- and 1,000-rupee notes had no cash value in an effort to tackle corruption and tax evasion.

Raju Sundaram, an office executive, said from outside a bank in the south Delhi area of Saket: "I am so angry at the lack of planning on the part of the government before taking such an enormous step."

Mr Sundaram, who had been in a slow-moving queue for four hours, said it was the third consecutive day that he was lining up outside his bank.

"On Thursday and Friday, they ran out of cash before my turn," he said.

Long queues were in place at major banks in central Delhi, as people waited to withdraw new currency notes.

But there were problems as more than half of the more than 200,000 cash machines in the country had not been reconfigured to dispense the new 2,000-rupee (£23) notes introduced by the government.

Meanwhile, anger is mounting as people, frustrated with the delays and long hours spent queueing, lost their cool, lashing out at the government and bank employees.

"If it's bad outside the bank, it's complete chaos inside," said housewife Suniti Kumar, as she elbowed her way out of a bank through a crowd.

Many banks ran out of cash, and bank staff who have been working long hours appeared helpless.

"This is a hugely disruptive step," said one teller in Delhi's shopping hub of Connaught Place, as he stepped outside for a cigarette.

"It required a lot more planning, but that didn't happen."

Delhi police said they received more than 3,000 emergency calls reporting fights and scuffles in the city on Friday as people crowded outside banks, waiting to exchange notes or withdraw money.

On Saturday, nearly 200 calls had been received in the first four hours since the banks opened at 9am local time, according to police.

In the southern city of Kollam, furious crowds smashed windows and vandalised a bank after the manager announced to waiting clients that the bank had run out of new notes.