ISTANBUL (Reuters) - The outlawed Kurdistan Workers Party (PKK) on Monday denied responsibility for a suicide bomb attack in Istanbul that wounded 32 people and said they were extending a cease-fire until Turkey's general elections in 2011.
Some officials had said the PKK, a guerrilla group that has fought a 26-year-long insurgency for autonomy in Turkey's southeast, was emerging as the most likely suspect for the attack on the police in central Taksim Square, a busy transport hub usually packed with foreign tourists and shoppers.
Istanbul, Turkey's largest city and its financial capital, has been targeted in the past by Kurdish separatists, al Qaeda and militants from the far-left.
"There is no way we would be involved in such an attack on a day our organisation was getting ready for a step towards peace and a democratic solution," the PKK said in a statement.
It also said it was extending a month-old cease-fire that expired on Sunday until Turkey's next elections in June 2011.
"Neither us nor any organisation linked to us have carried out or planned such an attack... We have no connection with the attack in any way," the statement said.
Small PKK cells have staged attacks in the past without authorisation from PKK headquarters and splinter groups including former PKK members have carried out bombings also.
Interior Minister Besir Atalay said no one had been detained in connection with the attack. He said the suspects would be disclosed once authorities were sure who was to blame.
State news agency Anatolian said the bomber used a type of explosive that has been used before by the PKK and by far-left groups, including the Revolutionary People's Liberation Party/Front (DHKP/C), which was involved in a 2001 suicide attack near Taksim on a police station that killed two people.
Anatolian said authorities have arrested in the last six months four suspected PKK bombers and two suspected DHKP/C bombers. On the day of the bombing police arrested 16 DHKP/C members.
Police released a picture of Sunday's bomber, showing a clean-shaven, heavy-browed man in his mid 20s or early 30s.
Financial markets shrugged off the bombing. The European Union candidate is favoured by foreign investors because of its strong growth, large domestic market and young population.
Prime Minister Tayyip Erdogan repeated a long-standing Turkish complaint that foreign countries fail to support Ankara's fight against terrorism. Turkey complains European countries allow free rein to sympathisers of the PKK, branded a terrorist organisation by Ankara, the United States and the EU.
"In some European countries, today even, there are groups known and proven to have links to the terrorist organisation which act freely under the mask of associations, foundations or the media," Erdogan said in a speech.
Some Turkish commentators suggested the attack could be the work of PKK hard-liners opposed to dialogue. The government refuses to negotiate with the PKK directly, but there have been reports of talks between Ankara and people close to the PKK.
Al Qaeda suicide bombers carried out a series of bombings in Istanbul in November 2003 that killed 62 people.
Several Islamist militants were arrested late last month but officials have played down chances that Islamists were involved in Sunday's attack.
Additional reporting by Ayla Jean Yackley; Writing by Ibon Villelabeitia; Editing by Louise Ireland