JNU SSS 2014 Question 34: Logic and proof techniques

Answer Question Nos. 32–34 on the basis of the following information :

Three individuals, $A$, $B$ and $C$, are suspected of income tax evasion. They testify under oath as follows :

$A$ : $B$ is guilty and $C$ is innocent.
$B$ : If $A$ is guilty, then so is $C$.
$C$ : I'm innocent but at least one of the others is guilty.

Assuming the innocent told the truth and the guilty told lies, who is innocent and who is guilty?