Sorry for your loss, but this is a common grandparent scam. Never wire money to someone you do not personally know. I've had those same calls. See: https://www.fbi.gov/news/stories/2012/april/grandparent_040212
Report it here: See: http://www.ic3.gov/default.aspx
Also report this to the people who sold you the wire transfer. I expect you used a moneygram or some such thing. You might not get your money back but at least they can be made aware of the scam.
Also go to your local police department and make a complaint. THere isn't much the police can do, but they can notify the community and the media.
Many of these sorts of scams originate in Canada. Canadian officials in the Anti-Fraud Call Center ask victims to report the fraud at their PhoneBusters hotline at 1-888-495-8501 .