How to validate XML data against DTD

Issue

I am trying to validate xml data against dtd file and tried using like below and it is throwing error as "Failed to resolve endpoint: validator://file:dtd/pce_security.dtd due to: The markup in the document preceding the root element must be well-formed."

    <doTry>
         <to uri="validator:file:dtd/pce_security.dtd"></to>
            <to uri="mock:valid"></to>
        <doCatch>
            <exception>org.apache.camel.ValidationException</exception>
            <to uri="mock:invalid"></to>
            <log message="Catch: Error in parsing ${body}"></log>
        </doCatch>
        <doFinally>
            <to uri="mock:finally"></to>
            <log message="Finally: Error in parsing ${body}"></log>
        </doFinally> 
       </doTry>     

By looking at web it seems camel validator does not support dtd. Could you please check and let us know how to validate xml data against dtd.