In my opinion, you should avoid using common words like “images”. It can be confusing for the system.
A previous post on SO nailed the use of images using Category ID. Here’s your edited code:
<?php
$your_category_ID = '1'
$query = new WP_Query( 'cat=$your_category_ID' );
if ( $query->have_posts() ) {
while ( $query->have_posts() ) : $query->the_post();
$src = wp_get_attachment_image_src( get_post_thumbnail_id($query->ID), array( 5600,1000 ), false, '' ); ?>
<a href="https://wordpress.stackexchange.com/questions/169970/<?php echo $src[0]; ?>" data-lightbox="image-77" data-title="<?php query->the_title() ?>">
<div class="item">
<div class="lazyOwl" style="background:url(<?php echo $src[0]; ?>) no-repeat center center;background-size:cover;height:300px;" alt=""></div>
</div>
</a>
endwhile;
/* Restore postdata */
wp_reset_postdata();
}
?>