Twig's if statement not working properly, why?

Question

Twig

{% for i in 0..9 %}
    <tr>
        {% for j in 0..9 %}
            <td id ="{{ i ~ j }}"
                    {% if gameArray[i][j] == "killed" %}
                        {{ 'class="killed"' }}
                    {% endif %}

            >
                {{  gameArray[i][j]}}
            </td>
        {% endfor %}
    </tr>
{% endfor %}

Now there is not a single cell with the value "kill" in the array, but it still assigns the class kill everywhere