An Israeli airstrike on the Gaza border killed a Palestinian on Thursday, health officials said, as tensions increased ahead of new protests. The health ministry named the man as Mujahid al-Khudari, 23, saying he died in Gaza Citys Shifa Hospital after being targeted by an Israeli strike near the border. The Israeli army earlier said an aircraft had "targeted an armed terrorist adjacent to the security fence", without specifying if the strike was conducted by a drone or other aircraft. It said the military would "not allow any harm to the security of Israeli civilians". Separately Thursday, the health ministry announced another man had died of wounds received last Friday when a protest by tens of thousands on the Gaza border led to clashes with Israeli forces. Shadi al-Kashif, 34, was shot in the head near the border in southern Gaza and had since been in critical condition, the ministry said. The death brings the toll for Fridays clashes to 18 Palestinians killed, with two more killed since the border protest. There have been no reports of Israelis injured. Tens of thousands of Palestinians began a six-week-long protest last Friday in tent encampments along the fenced border of the Israeli-blockaded Gaza Strip, an enclave of two million ruled by the militant Hamas group. The demonstrators are pressing for a right of return for refugees and their descendants to what is now Israel. Israel has faced calls for an independent investigation from the European Union and United Nations chief Antonio Guterres over last Fridays violence. Israel has rejected the calls, saying its soldiers opened fire when necessary to prevent attacks, attempts to damage the fence and infiltration. Palestinians say protesters were fired on while posing no threat to soldiers. Thousands are expected to rally along the border again on Friday. UN Middle East envoy Nickolay Mladenov on Thursday urged Israel to show “maximum restraint” and Palestinians to “avoid friction” during protests at the Gaza-Israel border. He voiced concern ahead of Friday, the Muslim sabbath, when the number of Palestinian protesters at the Gaza-Israel border is expected to increase. “I am following with concern the continuing preparations and rhetoric for this Friday’s ‘Great Return March’ in Gaza,” said Mladenov, the United Nations Special Coordinator for the Middle East Peace Process. “Israeli forces should exercise maximum restraint and Palestinians should avoid friction at the Gaza fence. Demonstrations and protests must be allowed to proceed in a peaceful manner. Civilians, particularly children, must not be intentionally put in danger or targeted in any way.”