Two bombs exploded only minutes apart in a packed pedestrian area of Istanbul on Sunday night, claiming 16 deaths and wounding more than 150 people in the deadliest assault against civilians in Turkey in approximately five years.

The city’s governor Muammer Guler said that the incident was part of a “terror attack” but authorities did not point the finger at any particular group, although Kurdish separatist militants were originally suspected.

The initial blast blew up in the residential neighborhood of Gungoren in a crowded square closed to traffic where people come together at night, witnesses reported, according to the Associated Press. Numerous people had hurried to the scene in order to find out what happened and lend a hand to the victims, when a second, more violent explosion went off very close by and just about 10 minutes after the first blast.

The assault was the country’s deadliest since November 20, 2003 when al-Qaida connected suicide bombings hit the British consulate and a British bank, killing at least 30 people.

Five days before, suicide truck bombs assailed two Istanbul synagogues, claiming 27 deaths. President Abdullah Gul condemned the Sunday attack of Istanbul in a written statement and explained that Turkey continued to be devoted to the struggle against terrorism, as he called it.

“Nothing can be achieved by terror, violently claiming lives of the innocent,” Mr. Gul said, as cited by the New York Times. “These attacks show the inhumanity and misery of the assailants.”

Authorities were maintaining investigations and examinations at both explosion locations in order to establish the exact cause and purposes of the attack, according to Turkish news organizations.