The IceCube Collaboration has recently announced the discovery of ultrahigh energy neutrino events. These neutrinos can be used to probe their production source, as well as leptonic mixing parameters. In this work, we have used the first IceCube data to constrain the leptonic CP violating phase δCP. For this, we have analyzed the data in the form of flux ratios. We find that the fit to δCP depends on the assumptions made on the production mechanism of these astrophyscial neutrinos. Consequently, we also use this data to impose constraints on the sources of the neutrinos. © 2014 American Physical Society.