Tens of thousands of Palestinians returned to the most heavily destroyed part of the Gaza Strip on Monday as Israel lifted its closure of the north for the first time since the early weeks of the 15-month war with Hamas in accordance with a fragile ceasefire.

Palestinian officials say more than 650,000 displaced people were blocked from entering the northern Gaza Strip, according to Reuters. Israel blocked access to the region after it accused Hamas of failing to release 29-year-old Arbel Yehud during an agreed upon hostage-prisoner exchange.