Palestinians in northern Gaza reported fierce air and artillery strikes early Monday as Israeli troops backed by tanks pressed into the enclave with a ground assault that drew increased international calls for the protection of civilians.

Israeli airstrikes hit areas near Gaza City¡¯s Shifa and al-Quds hospitals, and Palestinian militants clashed with Israeli forces in a border area east of the city of Khan Younis, in the enclave¡¯s south, Palestinian media reported.

There was no comment from Hamas or the Israeli military on the fighting early Monday. Journalists were not able to confirm the reports.