API v2 Issue when creating a ticket with attachment

Hi, I've got an issue when trying to create a ticket via API v2.

I'm using PHP curl, and the details I'm passing are as follows:

array (size=7)
  'description' => string 'Test Test Test Test Test Test Test Test Test Test Test' (length=54)
  'subject' => string 'Mail subject' (length=12)
  'email' => string 'me@danielbell.co.uk' (length=20)
  'priority' => string '1' (length=1)
  'status' => string '2' (length=1)
  'group_id' => int 6000197799
  'attachments' => 
    array (size=1)
      0 => string '@/public/uploads/f3028783684500f6e99bbcb7edb549fa117c76ac.jpg' (length=61)

Here's what I'm actually passing via the CURL_POSTFIELDS (I've stripped 0 from the array so it's attachments[] and not attachments[0]:

description=Test+Test+Test+Test+Test+Test+Test+Test+Test+Test+Test&subject=Mail+subject&email=me%40daniel-bell.co.uk&priority=1&status=2&group_id=6000197799&attachments%5B%5D=%40%2Fpublic%2Fuploads%2Ff3028783684500f6e99bbcb7edb549fa117c76ac.jpg

description=Test+Test+Test+Test+Test+Test+Test+Test+Test+Test+Test&subject=Mail+subject&email=me%40daniel-bell.co.uk&priority=1&status=2&group_id=6000197799&attachments%5B%5D=%40%2Fpublic%2Fuploads%2Ff3028783684500f6e99bbcb7edb549fa117c76ac.jpg

And the following is an error I'm getting:

array (size=2)
  'description' => string 'Validation failed' (length=17)
  'errors' => 
    array (size=1)
      0 => 
        array (size=3)
          'field' => string 'attachments' (length=11)
          'message' => string 'Should be a valid format' (length=24)
          'code' => string 'datatype_mismatch' (length=17)

Can you advise on what I'm doing wrong and how to get the attachments working?

Thanks in advance.