ClassNotFound: JsonSchemaFactory

I am using following dependency in pom. xml. It works fine

<dependency>
    <groupId>com.github.java-json-tools</groupId>
    <artifactId>json-schema-validator</artifactId>
    <version>2.2.11</version>
</dependency>

But if I include all the JARs downloaded by maven as external jar it throws ClassNotFound Error for com.github.fge..jsonSchema.JsonSchemaFactory.class