UN Secretary-General Ban Ki-moon "remains concerned about ongoing clashes between protesters and security personnel" and "saddened by the deaths and injuries that have occurred," deputy UN spokesman Eduardo del Buey said.

Criticism over the Turkish government's actions has come from the United States and several other nations over three weeks of unrest that has led to the deaths of four people and injured more than 5,000.

"The Secretary-General urges maximum restraint and the pursuit of constructive dialogue in order to resolve differences and avoid further violent confrontation," del Buey said. "He believes that stability is best assured through such dialogue and when the rights to peaceful assembly and the freedom of expression are fully respected."

What began as an environmentalists' sit-in at Istanbul's Gezi Park, near the new focal point of Taksim Square, has grown into widespread demonstrations against the government and police. A sometimes-violent response to the park occupation prompted further protests.

'Only provocateurs'

Turkish Interior Minister Muammer Guler said on Tuesday that 62 people were arrested in Istanbul, the country's biggest city, while many others were detained in the capital, Ankara. Police confirmed the arrests and said: "For now, only provocateurs will be taken for questioning."

Performance artist Erdem Gunduz appeared to have become a talisman for anti-government protests in Turkey on Tuesday after an eight-hour silent vigil in Taksim Square, which earned him the nickname "the Standing Man."

Over the weekend, police had cleared out the square and shut it down to protest - but left it open to pedestrians. Gunduz took to the square and simply stood there.

Others gradually began to join him, and silent protests took hold across the country. In Ankara, the capital, for example, a woman stood still at the spot where the police had killed a protester.

Police dispersed the crowd around Gunduz on Tuesday morning, but later in the day protesters resumed the silent vigil.

mkg/rc (Reuters, AFP, AP)