Gunfire Heard outside Istanbul's Dolmabahce Palace

Two militants on Wednesday launched an attack with guns and explosives on the Dolmabahce Palace in Istanbul, one of Turkey's main tourist attractions which also houses offices of the prime minister, the Istanbul authorities said in a statement.

Initial reports had said gunfire and an explosion was heard outside the palace, which was crowded with tourists at the height of the summer season.

"Members of the terrorist organization launched an attack with weapons and hand grenades," the Istanbul governor's office said in a statement.

It added that the suspects had targeted the police who stand on ceremonial guard outside the Ottoman-era palace during the day.

The two attackers -- carrying two hand grenades, an automatic rifle, a gun and other ammunition -- were caught by police, the statement said, adding that there were no fatalities.

Security sources speaking to the state-run Anatolia news agency however said that a policeman was lightly injured in the attack.

Private NTV television earlier said that the suspects had been caught in the vicinity of the German consulate.

There was no immediate claim of responsibility for the attack, but Anatolia said that the suspects were members of the radical left wing Revolutionary People's Liberation Front (DHKP-C).

The DHKP-C claimed a similar attack on the Dolmabahce Palace on January 1 where two grenades were hurled at the guards which failed to explode.

The militants were also behind an attack earlier this month on ruling Justice and Development Party's (AKP) headquarters in Istanbul, Anatolia said.

Police were hunting for at least one more suspect, Anatolia said.

Dolmabahce -- one of the last great palaces of the Ottoman Empire and also where the founder of modern Turkey Mustafa Kemal Ataturk, died in 1938 -- is one of Istanbul's major tourist attractions.

Part of the palace is open to the public but another wing hosts reception rooms and offices of Prime Minister Ahmet Davutoglu.

The incident came during growing tensions in Turkey as the government wages an unprecedented "anti-terror" offensive against jihadists and Kurdish militants.

It followed the overnight death of a 17-year-old boy during clashes in Istanbul between police and a group allied to the PKK.

So far, Turkey's operation has focused largely on the Kurdish rebels, who have responded by tearing up a 2013 ceasefire and waging a bloody campaign against the security forces.

Eight Turkish soldiers were killed on Wednesday in a bomb attack on their vehicle in the single most deadly strike to be blamed on the PKK since the hostilities started.

According to the government, more than 2,500 people have so far been detained in raids targeting suspected members of the PKK, IS and DHKP-C, the overwhelming majority of them from the PKK.