Jpa + jsp

Programação
,
#1

ERRO AO TENTAR DELETAR REGISTRO.

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package com.cleiton.consultasAtualizarDeletar;
import javax.persistence.EntityManager;
import javax.persistence.Query;

import javax.transaction.TransactionScoped;

import com.cleiton.topicos2.Consultar;

public class DeletarUsuario {

@TransactionScoped
public void deletarusuario(String codigo) throws Exception {
	
	
	Consultar consulta = new Consultar ();
	
	EntityManager obconsulta = consulta.getEntityManager();
	
	Query query= obconsulta.createQuery("DELETE CADASTRO_USUARIO U WHERE U.USR_CODIGO='"+codigo+"'");
	
       
       query.executeUpdate();
	((EntityManager) query).getTransaction().commit();

}
}

SEGUE O ERRO.

javax.persistence.TransactionRequiredException: Executing an update/delete query