Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said (in explanation of this verse): "Indeed, those whose souls the angels take while they were wronging themselves, (the angels) say: In what condition were you? They say: We were weak and helpless in the land. They say: Was not the earth of Allah spacious enough for you to emigrate in it? For those, their refuge is Hell, and what an evil destination it is" [Surah al-Nisa': 97]. He said: They were a group of Muslims in Makkah who went out with a party of the polytheists to battle and were killed along with them. Then this verse was revealed: "Except the weak among the men, women and children who are unable to devise a plan and are not guided to a way; for those, it is hoped that Allah will pardon them" [Surah al-Nisa': 99]. So Allah excused those of them who had an excuse, and destroyed those who had no excuse. Ibn Abbas (may Allah be pleased with them both) said: "My mother and I were among those who had an excuse."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11658