The Turkish authorities committed "gross human rights violations" during anti-government protests that rocked the country in June, Amnesty International said in a report released on Wednesday.
"The attempt to smash the Gezi Park protest movement involved a string of human rights violations on a huge scale," Andrew Gardner, the London-based watchdog's Turkey expert, said in a statement.
"They include the wholesale denial of the right to peaceful assembly and violations of the rights to life, liberty and the freedom from torture and ill-treatment," he added.
What started as a relatively small environmentalist movement to save Istanbul's central Gezi Park from re-development evolved into a nationwide wave of protests against Prime Minister Recep Tayyip Erdogan, who is seen as increasingly authoritarian.
The Turkish police's crackdown was often heavy-handed. Six people were killed and more than 8,000 injured during the protests, according to the Turkish doctors' union.
Amnesty -- detailing the use of live ammunition, tear gas, water cannon, plastic bullets and beatings -- said the deaths of at least three protesters were linked to the "abusive use of force by police."
The police "routinely" fired directly at protesters, bystanders and sometimes into residential buildings and medical facilities, resulting in hundreds of injuries, according to witnesses interviewed by the rights group.
The Amnesty website carried a video accompanying the report's release and entitled "When Turkey took torture to the streets".
The report said the wave of violence had harmed Turkey's ambition to become a democratic model for Muslim countries and "exposed a striking intolerance of opposing voices."
The watchdog said there was still time for Turkey to comply with international laws and conventions in the unrest's aftermath, which has seen the regime take a tough line on protesters.
"The vast majority of police abuses already look likely to go unpunished, while many of those who organised and participated in the protests have been vilified, abused - and now face prosecution on unfair or inflated charges," the report said.