Sheikh Naim Qassem has been the acting head of Hezbollah since its longtime leader Sayyed Hassan Nasrallah was killed as part of an Israeli offensive that has taken out many of the group's senior officials.

Qassem made a defiant televised speech Tuesday, claiming that the group's military capabilities are intact and Israelis will only suffer further as fighting continues.

Israel's military struck outside the gates of a hospital in southern Lebanon without warning on Friday, killing seven paramedics and forcing the facility to close, the hospital director told The Associated Press a day after one of the most deadly attacks on health workers in the weeks since fighting escalated between Israel and Hezbollah.

The account of the Friday airstrikes that flung hospital doors off their hinges and shattered glass was the latest to detail attacks that Lebanon's health ministry says have killed dozens of health workers.

Israel launched a new air and ground offensive in northern Gaza Sunday, hours after pounding Beirut's southern suburbs in the heaviest bombardment since it stepped up its pursuit of Hezbollah last month.

The intensified campaign on two fronts, including an overnight strike on a Gaza mosque that killed 19, came as Israel remained on high alert ahead of memorial events to mark the surprise attack a year ago that triggered the ongoing war.