ISTANBUL, Turkey - Bomb blasts that killed 17 people and injured 150 others in a crowded neighborhood square appeared to be linked to a Kurdish rebel group, Istanbul's governor said Monday, though the rebels immediately denied involvement.
Gov. Muammer Guler said police were still investigating the Sunday night explosions, the deadliest attack against civilians in Turkey in five years.
"There appears to be a link with the separatist organization. We are working on that. We hope to get a result at the first opportunity," Guler told reporters.
A pro-Kurdish news agency, Firat, reported that a Kurdish rebel leader said the Kurdistan Workers' Party, or PKK, did not carry out the bombing.
"The Kurdish freedom movement has nothing to do with this event, this cannot be linked to the PKK," Firat quoted the leader, Zubeyir Aydar, as saying. "We extend our condolences to the families of the victims and to the Turkish people."
Officials described the blasts as a terrorist attack, though nobody has claimed responsibility. Turkey is home to a variety of militant groups, including Kurdish rebels, Islamic extremists and alleged coup plotters with ties to the secular establishment.
"I feel deep grief from this cowardly attack that targeted innocent citizens and I curse them with hatred," said Gen. Yasar Buyukanit, the military chief. "The fact that the attack was carried out in a vibrant street at a time when there were crowds once again shows the savagery, the desperation and the bloody face of terrorism."
The attack happened on the eve of a court's deliberations on whether to ban the Islamic-oriented ruling party for allegedly trying to undermine secularism, and the timing raised questions about whether there was a link.
The attack and the legal challenge to the government highlight a growing mood of uncertainty in Turkey, where an Islamic-oriented government that won a strong mandate in elections last year is locked in a power struggle with secular circles that have backing in the military and judiciary.
The bombs went off in the residential neighborhood of Gungoren in a busy square closed to traffic where people congregate at night, witnesses said.
They appeared to be designed to inflict maximum casualties among civilians. Authorities said the vast majority of the 17 deaths and 150 injuries occurred when a curious crowd gathered after an initial, small blast.
"First, they exploded a percussion bomb to grab attention. Then, 10 minutes later, in another trash can, they exploded a fragmentation bomb," said Deputy Prime Minister Hayati Yazici.
Cihan news agency said the second bomb consisted of a plastic explosive of the same kind that was used in a suicide attack in a shopping thoroughfare in Ankara in May 2007 that killed 7 people. That attack was blamed on the PKK.
Two of the dead were children. Cihan said. Anatolia news agency said one victim was a 12-year-old girl who rushed with her parents onto the balcony of their fourth floor apartment to see what was going on after the first explosion.
Turkish police, following a tip from residents, detained three teenagers who were found late Sunday in the basement of an apartment near the scene of the explosions, Milliyet newspaper reported on its Web site Monday.
The three, ages 16 and 17, claimed they hid in the basement because they were frightened from the explosions, the paper reported.
Guler would not confirm the newspaper's report.
An Associated Press reporter who arrived shortly after the explosions saw at least 12 people lying on the ground. Broken glass, clothing, shop mannequins and other debris were strewn on the ground and bomb squads in white overalls were inspecting the scene.
Many of the injured waited for medical treatment, their faces and bodies covered with blood. Several people who appeared seriously wounded were wrapped in blankets and carried to ambulances waiting near the site of the blasts.
"The first explosion was in a telephone booth," said Huseyin Senturk, who owns a nearby shoe shop. "The second explosion was some 40 meters (yards) away."
The attack was the country's worst since November 20, 2003, when al-Qaida linked suicide bombings struck the British consulate and a British bank, killing at least 30 people. Five days earlier, suicide truck bombs attacked two Istanbul synagogues, killing 27.
On July 9, gunmen believed to be inspired by al-Qaida opened fire on police guarding the U.S. consulate in Istanbul, killing three officers. Three attackers also died in a shootout with police.
On Monday, Prime Minister Recep Tayyip Erdogan canceled a Cabinet meeting in the capital, Ankara, so that he could travel to Istanbul.
"No goals can be achieved with violence, killing innocent people and terrorism," President Abdullah Gul said in a statement. "These attacks show how inhumane and miserable the instigators are."
Both Erdogan and Gul are on a list of people that Turkey's chief prosecutor wants banned from joining a political party for five years as part of the case against the ruling Justice and Development Party. Even if the court decides to ban the party, its members could regroup under another name and form a new government.
The case before the top court is pivotal in that conflict, which has distracted attention from key policies such as Turkey's troubled bid to join the European Union. In another reflection of Turkey's rift, an Istanbul court plans to try 86 people, including former army officers, accused of plotting to provoke an armed uprising with the aim of bringing down Prime Minister Recep Tayyip Erdogan's government.