JERUSALEM (JTA) — Israel issued a travel warning for Turkey, calling on Israeli citizens currently residing in or visiting Turkey to leave immediately. The travel warning, which is upgraded from a basic concrete threat to a high concrete threat, was issued Monday, March 28 by the National Security Council Counter Terrorism Bureau, which is part of the Prime Minister’s Office. The warning comes a week after a suicide bombing in Istanbul killed three Israelis and one Iranian national. Turkish media later reported that the bomber targeted an Israeli tour group. Turkish Police issued a nationwide alert on Sunday, March 27, warning of possible Islamic State attacks over the weekend against churches and synagogues, and calling on consulates and embassies in the country to be on high alert. The Islamic State has been blamed for four of six bombing attacks in Turkey in the past eight months, the Turkish news service Hurriyet Daily News reported.

Last week, Turkish President Recep Tayyip Erdogan said in a telephone conversation with his Israeli counterpart that his country is “ready to cooperate with Israel against terrorism.”