Prime Minister Recep Tayyip Erdogan was due back in Turkey Thursday after a trip abroad, with thousands of angry demonstrators calling for his resignation as protests entered a seventh day.

Deputy prime minister Huseyin Celik has urged party supporters not to flock to the airport to welcome him back so as not to inflame tensions.

"The prime minister does not need a show of power," he told a local television channel, Wednesday.

When Erdogan flew out of Turkey Monday on a four-day visit to north Africa, he had dismissed the protests, saying they would have died down before he returned.

They were still going strong Wednesday, though that day saw the first confrontations between ruling party supporters and protesters.

In the Black Sea port of Rize, a group of 25 youths who staged an anti-government protest was attacked by a crowd of several hundred people, CNN-Turk television reported on Thursday.

Police fired tear gas to disperse supporters of Erdogan's Justice and Freedom Party (AKP) who had surrounded a building where some of the youths had taken shelter.

Some of the anti-government protesters were later hospitalised, but there was no word on their condition.

On Wednesday evening, police used tear gas and water cannon to disperse demonstrators in Ankara's central Kizilay Square.

The situation was quieter in Istanbul however, for the first time since the unrest began last Friday.

It was a heavy-handed response to a peaceful demonstration in Istanbul that sparked nationwide anti-government protests denouncing Erdogan, in power since 2002.

Most of the anger has been directed at Erdogan, who has dismissed the protesters as "extremists".

Turkey's Nobel Prize-winning novelist Orhan Pamuk blamed the government for the unrest in a scathing article published online by Hurriyet daily.

He denounced the authorities for having failed to consult the public over plans to redevelop the Istanbul park, the issue that sparked the initial protests on Friday.

"This insensitive policy is no doubt part of the ever more authoritarian and repressive attitude of the government," he wrote.

Internationally renowned pianist, Fazil Say, voiced support for the protests.

At a concert in the western port city of Izmir, he banged pots and pans before a concert Wednesday, a reference to nightly anti-government protests, local media reported

Delighted members of his audience responded in kind, chanting "Everywhere is Taksim, everywhere is resistance."

Say has had his own battle with the authorities: he has won a retrial for his conviction for blasphemy earlier this month.

Two people have been killed in the seven days of unrest nationwide, according to doctors and officials.

The national doctors' union has said more than 4,000 had been injured, 43 of them seriously, as police tried to quell the protests with tear gas, pepper spray and water cannon.

But Turkey, while acknowledging some police excesses, has hit back at criticism of its handling of the crisis, a Turkish foreign ministry source told AFP.

The diplomat, speaking on condition of anonymity, said Foreign Minister Ahmet Davutoglu had told US Secretary of State John Kerry in a phone call Tuesday: "Turkey is not a second-class democracy."

Turkey's Western allies have voiced concern in recent days over the police violence.

Davutoglu assured Kerry an investigation was under way into the police response.

He played down the demonstrations, likening them to the Occupy Wall Street movement in the US in 2011, the source said.

The tough police action has hardened Turkey's protest movement, drawing in labour unions that represent hundreds of thousands of people.

Erdogan's critics say he has become increasingly authoritarian. They have accused him of seeking to force conservative Islamic values on Turkey, a mainly Muslim but constitutionally secular nation.

In the premier's absence, Deputy Prime Minister Bulent Arinc on Tuesday apologised to wounded protesters and promised that the government had "learnt its lesson".

He met with representatives of some of the protesters, who urged him to sack the police chiefs in cities where officers had used excessive force and to ban the use of tear gas against protesters.

Sitting at the crossroads of East and West, Turkey has long aspired to join the European Union, which sets strict requirements on human rights for prospective members.

Erdogan's Justice and Development Party (AKP) first took power in 2002 and has won three elections in a row.

Erdogan has told protesters they should wait to express their views in elections next year, when observers expect him to run for president.