How to add class name using Vue.js to a table column which is part of a Vue.js Template?

Question

I need to assign class name from my visitor object (visitor.iso_code) to a table column. However Vue.js will not allow me to do it this way. I've tried v-bind:class and :class and neither of them work. Any help would be appreciated. Thank you in advance.

<template lang="html">
<div>

    <table id="vue_generated_visitors_table" class="table">
    </table>
         <tbody>
            <tr v-for="visitor in visitors_table">
                <th scope="row">{{ visitor.id }}</th>
                <td>{{ visitor.created_at }}</td>
                <td><img src="images/blank.png" class="{{visitor.iso_code}}" />&nbsp;{{ visitor.country }}</td>

                <td>{{ visitor.city }}</td>
                <td>{{ visitor.state_name }}</td>
                <td>{{ visitor.postal_code }}</td>
                <td>{{ visitor.lat }}</td>
                <td>{{ visitor.lon }}</td>
                <td>{{ visitor.timezone }}</td>
                <td>{{ visitor.currency }}</td>
                <td>{{ visitor.userAgent }}</td>
            </tr>
        </tbody>
    </table>
</div>
</template>

<script type="text/javascript">
export default {
    props: ['visitors_table','method'],
    data () {
        return {

        }
    },
    methods: {}
}