ISIS  attacked a monastery in the heart of the Sinai Peninsula on Tuesday, continuing its wake of terror targeting Christians in Egypt.

ISIS forces opened fire from a hilltop overlooking the police checkpoint situated about 800 yards from Saint Catherine’s Monastery, a popular tourist site in the heart of the Sinai Peninsula. One Egyptian police officer was killed and four others were injured. It is believed that some of the ISIS attackers were wounded before fleeing the scene. The Islamic State (ISIS) claimed responsibility for the attack via the ISIS-affiliated Amaq news agency.

Saint Catherine’s Monastery, part of the Eastern Orthodox Church, was built in the sixth century and is the oldest operating monastery in existence. This is the first time ISIS has attacked a monastery, but it comes ten days after an ISIS affiliated terror group attacked two Coptic Churches in Egypt, setting off bombs that killed 45 people. After the attack, Egyptian President Abdel-Fattah el-Sisi declared a three-month state of emergency. Tensions are high as this recent act of anti-Christian violence comes ten days before Pope Francis is scheduled to visit Egypt. ISIS sources stated the terror group will continue to target Christians in Egypt. Egypt, with ten percent of its 90 million people as Christians, has the largest population of Christians in the Middle East.

The US Government issued a travel warning on Wednesday, advising American citizens in Egypt to stay away from Christian places of worship for the next two weeks and to avoid crowds as long as they remain in the country. The Israeli Government issued a travel warning last week, instructing Israelis to leave the Sinai while banning more Israeli citizens from entering.