350 mensajes de alerta en 30 horas

Buenos días,

En poco más de un día, WordFence me ha enviado 350 mensajes de alerta del sito marcosdelrio.com (y subiendo) con el texto que pondré a continuación, Me gustaría saber a qué se debe y sobre todo cómo pararlo:

This email was sent from your website «Marcos Del Río» by the Wordfence plugin at Sunday 12th of April 2015 at 12:21:20 PM
The Wordfence administrative URL for this site is: http://www.marcosdelrio.com/wp-admin/admin.php?page=Wordfence
A user with IP address 186.220.110.238 has been locked out from the signing in or using the password recovery form for the following reason: Exceeded the maximum number of login failures which is: 20. The last username they tried to sign in with was: »
User IP: 186.220.110.238
User hostname: badc6eee.virtua.com.br

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