news_left = 0;
var news_timer;
var step = 30;

function startNewsLeft(id) {
    news_timer = window.setInterval("newsLeft('"+id+"');", 50);
}

function startNewsRight(id) {
    news_timer = window.setInterval("newsRight('"+id+"');", 50);
}

document.onmouseup = stopMove;

function stopMove() {
   window.clearInterval(news_timer);
}

function newsLeft(id) {
   newsRarrow = document.getElementById("news_rarrow");
   newsLarrow = document.getElementById("news_larrow");

   el = document.getElementById(id);
   news_left = news_left + step;
   if (news_left > 0) { 
      news_left = 0;
      newsLarrow.style.visibility = "hidden";
      newsLarrow.style.width = "0px";
   }
   el.style.marginLeft =  news_left + "px";

   newsRarrow.style.visibility = "visible";
   newsRarrow.style.width = "30px";
};

function newsRight(id) {

   newsRarrow = document.getElementById("news_rarrow");
   newsLarrow = document.getElementById("news_larrow");

   el = document.getElementById(id);
   news_left = news_left - step;
   max_left = - (el.offsetWidth - document.getElementById("news_block").offsetWidth);
   if (max_left > news_left) { 
     news_left = max_left;
     newsRarrow.style.visibility = "hidden";
     newsRarrow.style.width = "0px";
   }
   el.style.marginLeft =  news_left + "px";
   newsLarrow.style.visibility = "visible";
   newsLarrow.style.width = "30px";
};