Neha had been in her home in Savreji Kharg village in Deoria district, near the Nepalese border.
Paswan said other family, not involved in the attack, called a rickshaw to try and get Neha, then unconscious, to the hospital.
However, police allege the driver of the rickshaw attempted to get rid of Neha's body, with family finding her a day later hanging over a nearby bridge.
"They wouldn't let me accompany them so I alerted my relatives who went to the district hospital looking for her but couldn't find her," Paswan said.
Neha was found hanging from a bridge over the Gandak river.
Ten members of Neha's family have been charged with murder and destruction of evidence, including Neha's grandparents, uncles, cousins and the rickshaw driver.
Paswan said Neha's grandparents often clashed with the teenager over her desire to wear more modern clothes, instead of traditional Indian clothing.
In March, thousands of women took to social media to share photos of themselves in ripped jeans after a politician's tone-deaf comment triggered global outrage.
Tirath Singh Rawat, chief minister of the north Indian state of Uttarkhand said women wearing ripped jeans were setting a "bad example" for children.
"Kaynchi se sanskaarn [sharp manners] – showing bare knees, wearing ripped denim and looking like rich kids – these are the values being given now," he said at an anti-substance abuse forum.
"Where is this coming from, if not at home? What is the fault of teachers or schools? Where am I taking my son, showing his knees and in tattered jeans?
"Girls are no less, showing their knees. Is this good? While the Western world follows us, doing yoga … covering their body properly. And we run towards nudity.
"What we do, our kids follow. A child who is taught the right culture at home, no matter how modern he becomes, will never fail in life."
