Hugo not generating index and 404 .html files.

I seem to be having an issue with Hugo.

I am following their get started guide: http://ift.tt/2lU09rx

I have followed this steps:

1) Created new site:

$ hugo new site my-site

2) In that folder I then typed the command for the new theme:

$ hugo new theme mysite-theme

Every worked fine, the files are there. The problem is them when I try to render the site. I type in the command:

$ hugo

Which creates the /public folder and two files:

• index.xml
• sitemap.xml

However, according to the guide it is supposed to create 4 files:

• index.html
• index.xml
• sitemap.xml
• 404.html

Now, even though there is nothing to put in these files, it should still create the index.html and 404.html files.

Has anyone else encountered this problem? Have I done something wrong or missed a step?

Thanks in advance for the help