Aanchal Arora, 23, collapsed and could not be revived, the police say. Her friend Aashima also fell unconscious and is in the ICU.
Aanchal was from north Delhi and had gone with a group of friends to attend the concert at the Haryana Urban Development Authority ground. Police sources say the venue was packed with a bigger crowd than it could possibly manage.
Aanchal may have died of a cardiac arrest due to suffocation, say the police, but it will be confirmed only by a post mortem report.
A doctor said Aanchal hadn't had any food or drink for several hours and her stomach and intestines were completely clean. "It could be exhaustion and overcrowding that hit her," he said.
When she fell to the ground, her friends tried to wake her and then took her to a hospital, where she was declared dead.
One report quotes a doctor as saying that she could have fainted because of a sharp drop in her pressure and heart rate.
The police say they were informed that the venue would have a maximum of 8,000 people, but at least 2,000 more showed up to hear Skrillex, a six-time Grammy winner.
In the past, artists like Enrique Iglesias, Atif Aslam and Arijit Singh have performed at the same venue.
Aanchal, the police say, was the youngest in her family.
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