The Israeli military acknowledged on Monday that Palestinian civilians were harmed at aid distribution centers in the Gaza Strip, saying that Israeli forces had been issued new instructions following what it called "lessons learned."

Since Israel lifted an 11-week aid blockade on Gaza on May 19, allowing limited U.N. deliveries to resume, the United Nations says more than 400 Palestinians have been killed while seeking handouts of aid.

"Following incidents in which harm to civilians who arrived at distribution facilities was reported, thorough examinations were conducted in the Southern Command and instructions were issued to forces in the field following lessons learned," the Israeli military spokesperson said in a statement.