I exported all the wp blog posts using the default wordpress export tool. Then i imported the xml file using the default import tool. There were 2 xml files in the zip file which I extracted. I uploaded the first one. Within 5 minutes I saw the posts were published and under the media library the images from the old blog where uploaded but when I checked the posts it contained the image domain links of old wp blog it wasn't linking to the images in the media library of my new blog which means if I delete the images from my old blog then the images will be unavailable in the blog posts of my new wordpress blog. Both the blogs are using fee wordpress sudomain I am not using any custom domain.