Israeli Prime Minister Benjamin Netanyahu said Israel’s actions on the Gaza border, where dozens of Palestinians were killed during mass protests on Monday, were self-defense against the enclave’s ruling Hamas group, Reuters reported.

“Every country has an obligation to defend its borders,” Netanyahu wrote on Twitter. “The Hamas terrorist organization declares it intends to destroy Israel and sends thousands to breach the border fence in order to achieve this goal. We will continue to act with determination to protect our sovereignty and citizens.”