Sentence:  From the east to the west coast of the Korean peninsula was a strip of land in which fear filled men were at that same moment furtively crawling through the <WSD>night</WSD> , sitting in sweaty anticipation of any movement or sound , or shouting amidst confused rifle flashes and muzzle blasts . 
Meaning of the word marked with <WSD> tags:  the time after sunset and before sunrise while it is dark outside