An estimated 100,000 Palestinians have fled to the crowded southern Gaza city of Rafah in recent days, the U.N. humanitarian agency said. Rafah is one of the only parts of Gaza that is not facing intense ground fighting, according to the agency, though a missile strike Thursday near Rafah’s Kuwaiti Hospital killed at least 18 people and wounded dozens, the hospital director said. Farther north in the besieged enclave, the Israel Defense Forces on Friday announced an expansion of its operations in Khan Younis.