This doesn’t make sense to me. Why would homicide bombers be carrying their passports? They were planning to blow themselves up - why bother with passports? And if they did have their passports on them when their vests exploded, how did the passports survive?
Based on the little I’ve heard, not all the attackers were suicide bombers.
Some were gunmen who hoped to escape after carrying out their attacks.
Maybe the passports were on gunmen killed by the police.