ISTANBUL: A militant group allied to Turkey's outlawed Kurdish party has shot dead in Istanbul an alleged member of ISIS who had fought in Syria, media said Thursday.

The reports come amid soaring tensions in Turkey following Monday's suicide bombing in the town of Suruc on the border with Syria that killed 32 and that the authorities blamed on ISIS.

The man, named as Mursel Gul, was assassinated late Tuesday in Istanbul, Turkish media including the Hurriyet daily and state Anatolia news agency reported.

The Patriotic Revolutionary Youth Movement (YDG-H), seen as the youth wing of the outlawed Kurdistan Workers Party (PKK), claimed responsibility for the killing in a statement, reports said.

The YDG-H statement said that the man had come to Istanbul seven months ago to receive treatment after being wounded while fighting with ISIS against Kurds for the flashpoint town of Kobani in Syria.

The group said it had been tracking his movements for three months and alleged Gul had himself been planning attacks in Istanbul.

"We will continue our operations against the ISIS gang and have identified many of them and will execute and punish them," it added.

"The Suruc murderers will be brought to account," it said.

Anatolia said the the killers, posing as cleaning salesmen, had fired four bullets into Gul's body.

Anti-terror police launched an investigation and have found no links between Gul and ISIS, it added.

The PKK's military wing had Wednesday claimed the murder of two Turkish police as revenge for the Suruc bombing, raising fears the fighting raging in Syria between Kurds and ISIS is spilling over onto Turkish territory.

Many Kurds in Turkey are deeply unhappy with the lack of support given by the Turkish government to the fight against ISIS in Syria and accuse Ankara of collaborating with the group, claims it denies.

Meanwhile, Turkish media reports said an Islamist named Ethem Turkben had been murdered by masked men at his home in the southern city of Adana in a killing also suspected to have been carried out by PKK-allied militants.

The PKK has waged a decades-long insurgency for self-rule for Kurds in the southeast that claimed tens of thousands of lives.

It declared a truce in 2013 after the government opened secret peace negotiations with its chief Abdullah Ocalan but the current violence has put this under threat.