Unfortunately, to me it does not give impression of being Lagunaria petersonia (Malvaceae). Kindly have a look at the fruit with seeds of this plant in this link:
The photograph you provided is a species of the Genus Lagunaria of the family Malvaceae, but on the basis of the fruit and seed structure I have some confusion regarding the species probably it is not L. patersonia as considered by Dr. Arvind and others.
Thanks Jacob for providing scale and good supplementary material. Did you observe flower of this plant?
Sunit:
Sunit, what features in your opinion makes you believe that it is genus Lagunaria (Malvaceae), which to our knowledge continues to be a monotypic genus with a solitary species: L. patersonia.