After a massive power outage left more than 300 million without electricity in Delhi and most of Northern India, things got worse on Tuesday.

When three regional power grids collapsed, some 620 million people were left without government-supplied electricity, making for the world's largest blackout. Serious concerns about the growing country's infrastructure and ability to meet its energy needs have cropped up, as millions were left cut off for hours on end.

Stalled trains, bumper-to-bumper gridlock and haircuts by dark are just a few of the highlights (or perhaps lowlights) from the photos coming out of India. Take a look at the scenes of a powerless population of millions.

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  • A traffic jam following power outage and rains at the Delhi-Gurgaon road on the outskirts of New Delhi, India, Tuesday, July 31, 2012. (AP Photo)

  • An Indian barber holding a candle, has a haircut for a customer at his shop in Kolkata, India, Tuesday, July 31, 2012. (AP Photo/Bikas Das)

  • A building is seen dark following a power outage in Kolkata, India, Tuesday, July 31, 2012. (AP Photo/Bikas Das)

  • A young Indian girl looks out from a stalled train window as passengers are stranded following a power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Rajesh Kumar Singh)

  • An Indian man watches as he and others wait inside a stalled train for its services to resume following a power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Rajesh Kumar Singh)

  • Indian stranded passengers wait for train services to resume at a railway station following a power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Rajesh Kumar Singh)

  • Indian stranded passengers wait for the train services to resume at a railway station following a power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Rajesh Kumar Singh)

  • Stranded passengers walk on railways tracks near parked trains following a power outage at a railway station in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Rajesh Kumar Singh)

  • Indian stranded passengers wait on a platform and some of them on rail tracks for the train services to resume following a power outage at Sealdah station in Kolkata, India, Tuesday, July 31, 2012. (AP Photo/Bikas Das)

  • A stranded Indian train passenger rests inside a railway coach as he waits for the train service to resume following a power outage in Kolkata, India, Tuesday, July 31, 2012. (AP Photo/Bikas Das)

  • An Indian shopkeeper fixes an electric generator at his shop in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Tsering Topgyal)

  • Pigeons sit on electricity wires along a Metro line after Delhi Metro rail services were disrupted following a power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/Mustafa Quraishi)

  • A handwritten notice about power failure is pasted outside a Metro station after Delhi Metro rail services were disrupted following power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/ Manish Swarup)

  • Commuters wait in line at a Metro station after Delhi Metro rail services were disrupted following power outage in New Delhi, India, Tuesday, July 31, 2012. (AP Photo/ Manish Swarup)