Done I think my island was griefed..

I logged on today which i havent done for a few days and i saw a few mobs at one of my buildings so i went to kill them. as i got closer i noticed a few blocks missing from the outside so i went in and i saw a hole was in the building. a big hole too. i dont know if there is a way to find out if someone did it or what caused it so i am posting here.
My MC name is same as forums.
Pictures:

 

Yes it was protected. It was kind of close to my base but was no where near the edge of my protection

 

is there anyway i can find out who or what did it? None of my other island members have been on during the days it would have happened. they only play when they find me on

 

Could a @Moderator look into this?

 

If the grief hasn't been dealt with already, I can investigate.[DOUBLEPOST=1444603795,1444603018][/DOUBLEPOST]As it turns out, this was due to fire. Probably from a boss mob, who can burn wood and make things explode. The only advice I can give you is to use different materials so fireballs can't break blocks in your base. :\

Thanks for your submission.

 

Thanks for that. didnt know any mobs could do that except maybe a blaze not sure.

 

Many boss mobs have this ability. But no problem.