A missile struck an Egyptian resort town about 220 km (135 miles) from the Gaza Strip early on Friday.
According to the Egypt’s Al Qahera News report, the missile hit a medical facility in Taba, injuring at least six people.
Taba straddles Egypt’s border with Israel’s Red Sea port of Eilat.
Israel’s military said it was aware of a security incident outside its borders.
There was no immediate claim of responsibility after Friday morning’s blast.
Taba, in Egypt’s Sinai Peninsula, is popular with tourists. It is about a three-hour drive from Egypt’s Red Sea resort town of Sharm el-Sheikh.