Turkish newspapers carried front-page pictures on Monday, March 21 of three more men believed to be planning suicide bomb attacks for Islamic State, after a suspected member of the radical militant group killed three Israelis and an Iranian in Istanbul, Reuters reports.

Sunday's attack on Istiklal Street, a long pedestrian avenue lined with international stores and foreign consulates, was the fourth suicide bombing in Turkey this year. Two in Istanbul have been blamed on Islamic State, while the two others in the capital Ankara have been claimed by Kurdish militants.

At least half a dozen newspapers from across the political spectrum carried head-and-shoulders pictures of three suspected Islamic State members, saying they had been given instructions to carry out further attacks in crowded areas, primarily in Istanbul.

"All provincial police units have taken action to try to capture the three terrorists suspected of being Islamic State members planning sensational attacks," the state-run Anadolu news agency said, citing unnamed security sources and describing them as part of an "active cell" in Turkey.

Turkey is part of a U.S.-led coalition against Islamic State in Syria and Iraq, but is also battling Kurdish militants in its southeast, a conflict President Tayyip Erdogan sees as fueled by Kurdish militia gains in Syria.

Interior Minister Efkan Ala on Sunday identified the Istanbul bomber as a man born in 1992 and from the southern province of Gaziantep near the Syrian border, adding that five people had been detained so far in connection with the blast.