People stroll at Istiklal street, a major shopping and tourist district, in central Istanbul, Turkey March 22, 2016. REUTERS/Osman Orsal

JERUSALEM (Reuters) - Israel urged its citizens visiting Turkey to leave “as soon as possible” in an upgraded travel advisory on Monday predicting possible follow-up attacks to the March 19 suicide bombing in Istanbul blamed on Islamic State.

Three Israeli tourists and an Iranian were killed in the Istanbul attack, which prompted the counter-terrorism bureau in Prime Minister Benjamin Netanyahu’s office to issue a generalized “level 3” warning against travel to Turkey.

A statement by the bureau raised this to “level 2” on Monday, signifying what it called a “high concrete threat” that Islamic State or similar groups would attack Turkish tourist attractions. It did not elaborate on what prompted the alert.

A senior diplomatic source said the advisory was intended only for Israeli tourists, not for dual-nationals living in Turkey, and that the update was issued in line with the latest information from the Turkish authorities.

President Tayyip Erdogan’s spokesman, when asked at a briefing about the Israeli advisory, said the move had followed Turkey’s own warnings to its citizens. But he urged countries against playing into the militants’ hands, after a series of security alerts from foreign diplomatic missions in Turkey.

“One should refrain from moves that lead to the suspension of daily lives, in a way which would be welcomed by the terrorists,” presidential spokesman Ibrahim Kalin said.

The Israeli statement said Israelis should avoid going to Turkey and, if already there, “depart as soon as possible”.

If a “level 1” alert were by issued by Israel, that would urge citizens to leave the country “forthwith”.