Trying to install but get HTTP500

I am trying to install but getting HTTP 500 error. Detail of the error:

PHP Parse error:  syntax error, unexpected 'class' (T_CLASS), expecting identifier (T_STRING) or variable (T_VARIABLE) or '{' or '$' in index.php line 24

<p>I am trying to install but getting HTTP 500 error. Detail of the error:</p><br /> <p>PHP Parse error:  syntax error, unexpected 'class' (T_CLASS), expecting identifier (T_STRING) or variable (T_VARIABLE) or '{' or '$' in index.php line 24</p>

It happened due to my PHP version. I edited it to 5.6 it solved.

<p>It happened due to my PHP version. I edited it to 5.6 it solved.</p>