Today I got a call from this number too. Same description as everyone else's here. A guy with Indian accent left a voice message claiming there is security issue with immigration bureau threatening legal action if we don't reply his call.
Some guy with an indian accent stated that legal action will take place if I dont respond. I tried to contact 415 251 3769 and it said it's the Internal Revenue Service.
They tried me too. Somebody by the name of Kevin. Right. Anyway I told them that the US government has declared all Indian phone scammers to be terrorists. Told him the NSA is monitoring all calls from India and that a Hellfire missile may soon drop in unexpectedly at his call center.
He hung up fast sounded like he dropped the phone or got out of his desk too quickly because there was a crashing sound before he hung up.