Israel has told its citizens to leave Turkey immediately amid fears of reprisal attacks after a deadly strike on a hospital in the Gaza Strip, a consular spokesperson confirmed to Agence France-Presse Wednesday.

"All Israelis staying in Turkey must leave as soon as possible," Israel's National Security Council announced late on Tuesday.

"I can confirm that the travel warning of the National Security Council to Turkey has been raised to 4, the highest level," the spokesperson told AFP.

Israel and Palestinians accused each other of the strike that hit the hospital in Gaza, which triggered a wave of protests in the region against Israel.

Thousands joined protests in Istanbul and the capital Ankara outside Israel's diplomatic missions to condemn the attack.

Turkish police detained five protesters for attempting to sneak into the Israeli consulate in Istanbul, the governor's office said.

Turkish President Recep Tayyip Erdogan, a fervent supporter of the Palestinian cause, accused Israel of "striking a hospital sheltering women, children and innocent civilians" and urged the world to stop the tragedy in Gaza.