VISA Renewal Procedure for tourists in USA

[PSingla]

Hi,
My parents are visiting US and there VISA is going to expire on 27th September 2017. They will be here till July end.
I would like to know the exact procedure to get their tourist visa renewal here in US. I looked at one of the link that says: they just have to go for finger printing.

Here is the link: https://www.immihelp.com/fingerprint...-for-usa-visa/

I would like to know more about the procedure and what all they will need to get it renewed.

Looking forward to get some suggestions.

Thank you,
Purvi

[Bayfield]

Not possible to renew a visa in the US, something they would do at their local Consulate.