var currentLoad = 9;

$(document).ready(function() {
    $('.newsOverviewBlock .item:lt('+ currentLoad + ')').addClass('active');
    checkButton();
    
    $(document).on("click",".newsOverviewBlock .loadMore", function() { 
        currentLoad = currentLoad + 4;
        $('.newsOverviewBlock .item:lt('+ currentLoad +')').addClass('active');
        checkButton();
    });
    
});

function checkButton(){
    if($(".newsOverviewBlock .item").length <= currentLoad){
        $(".newsOverviewBlock .loadMore").hide();
    }
}