The attack is the fifth in Turkey's largest city this year.
Authorities hold one Turkish national and two from Dagestan after tip-off about plot.
Unless this is done, Ban Ki-moon's showcase event should be judged a failure, says War Child UK.
The U.S. embassy has warned Americans that there are 'credible threats' to tourist areas in Turkish squares.
Turkey's leader said his government has "nothing to discuss with terrorists."
One of the club's biggest stars could be on his way out of Old Trafford.
The suspected ISIS bomber killed three Israelis in Turkey's largest city on Saturday.
The German government said it had received "concrete indications" that an attack was planned.
The Kurdistan Freedom Falcons warns it will strike again in the country.
The president's proposal comes after the third Ankara bomb blast in just six months.
The world is ignoring the Kurdish plight in southeastern Turkey, writes HDP leader Selahattin Demirtas.
The country's largest newspaper ran pro-Erdogan stories after the government raided it on Friday.
There were no casualties in the incident in Istanbul.
The shooter fired bullets as a tip after becoming furious at paying more for his caffeine hit.
More than 1,000 people signed a declaration against the clashes in southeastern Turkey.
In their sixth debate, expect the Republicans to discuss the economy, immigration and North Korea.