Cannot show image by img.src

I have no idea why setting img.src with import is fine but when I pass the path to it doesn’t work.

import mahjong_tiles from '../assets/mahjong_tiles/1man.png'

const displayTileArr = () => {
    var img = document.createElement('img');
    img.src = mahjong_tiles ; //OK
    img.src = '../assets/mahjong_tiles/1man.png';  //NOT OK
    document.getElementById('display-hand').appendChild(img);   
}