Turkish riot police used tear gas and water cannon in a dawn raid Friday to end a peaceful sit-in by hundreds of people trying to prevent trees from being uprooted at an Istanbul park. The move ignited furious protests and clashes that injured at least 12 people.

The protest then spread to the capital Ankara, where hundreds of others gathered at a park and chanted anti-government slogans in solidarity with those in Istanbul.

In a victory for the protesters, an Istanbul court later ordered the temporary suspension of the project to uproot the trees.

Police took action on the fourth day of the protest against a government plan to revamp Istanbul's main square, Taksim. Officers clashed with angry demonstrators in surrounding areas, firing tear gas canisters and pushing people back with water cannon.

Several protesters were injured when a wall they climbed on collapsed during a police chase, and at least two people — including a journalist — were hit in the head by tear gas canisters. Two opposition legislators were among several hospitalized after being affected by the gas, the private Dogan news agency reported.

The protesters were demanding the square's Gezi Park be protected from plans that include the construction of a shopping mall. Many also aired grievances against Prime Minister Recep Tayyip Erdogan's Islamic-rooted government, which has been seen as displaying increasingly authoritarian tendencies in its third successive term.

Controversial bridge

Last week, the government enacted a law restricting the sale and advertising of alcohol, a move that has alarmed secular Turks.

Earlier this week, the government went ahead with a ground-breaking ceremony for the construction of a disputed third bridge across the Bosporus Strait that some say will destroy the few remaining green areas of the sprawling city. It also named the bridge after a controversial Ottoman sultan believed to have ordered a massacre of a minority Shia Muslim group, instead of choosing a more unifying figure.

Protesters in Gezi Park held up a large poster Friday with a caricature depicting Erdogan as an Ottoman sultan with a caption that read: "The people won't yield to you."

Erdogan dismissed the protesters' demands, saying the government would go ahead with the renovation plans "no matter what they do." The forestry minister said more trees would be planted than those uprooted at Gezi.

The dawn raid was the latest in a series of aggressive crackdown on protests. Human rights activists frequently accuse Turkish police of using inordinate force to break up protests and of excessively using tear gas and pepper spray against protesters.

12 to hospital

Interior Minister Muammer Guler said that authorities would investigate the reports of disproportionate use of force by police at Taksim. Still, he defended the crackdown, saying officers were carrying out their duties against an illegal occupation of the park.

Istanbul Gov. Huseyin Avni Mutlu said 12 people were treated in hospitals for injuries and least 13 people were detained.

The media rights group Reporters without Borders said the injured journalist, Ahmet Sik, and others were deliberately targeted by police and urged Turkish authorities to halt the "excessive" use of force. A Reuters photographer was also injured.

Amnesty International also deplored what it called Turkish police brutality and said some officers should be brought to justice.

Demonstrators affected by the gas sought shelter at a luxury hotel at Taksim and were tended by guests. Police removed tents and the demonstrators' belongings and mounted barricades around the park.

In Ankara, some 500 people crammed into a small park close to many embassy buildings, calling on the government to resign.