Three people have been sentenced to death for organising the attack in Tiananmen Square last October that left five people dead.
A court in Urumqi , Xinjiang convicted the three of organising and leading a terrorist group and endangering public security, Xinhua reported. They were identified as Husanjan Wuxur, Yusup Umarniyaz and Yusup Ahmat.
Five other defendants were sentenced to prison terms ranging from five years to life for their part in organising the attack.
Meanwhile, 13 people were executed in three cities in Xinjiang after being earlier convicted for "terrorist attacks and violent crimes", state media reported. The incidents dated back to February 2012. The sentences were carried out following a review by the supreme court.
Watch: Three sentenced to death as court reveals unseen footage of Tiananmen Square attack
On October 28, a car ploughed into tourists near the entrance to the Forbidden City in Beijing and burst into flames. A Chinese visitor and a tourist from the Philippines were killed. The attackers - the driver of the car, his wife and his mother-in-law - also died. The authorities blamed Muslim separatist militants from Xinjiang.
The suspects formed a terrorist group in 2011 and plotted violent acts, state television reported. From December 2012 to the following September they acquired firearms and explosives and plotted to go to the capital to set off a deadly explosion.
Members of the group travelled to Beijing in October and raised money from supporters to buy the car that would be driven to Tiananmen Square.
About 400 people attended the public trial of the suspects, and footage showed Uygur women in tears as they watched the proceedings.
Li Wei, a Beijing-based anti-terrorism expert, said the death sentences would do little to deter militants from carrying out future attacks. "Terrorists' minds have long been implanted with extreme thoughts. They understand what consequences they face," Li said.
Human rights organisations say curbs on the ethnic group's language, religion and culture have inflamed tensions.
The Tiananmen attack was the first of several that the authorities have blamed on Uygur separatists in recent months.
These include an attack on an open-air market in Urumqi in which assailants killed 29 people.
On Sunday, four people were injured when attackers armed with knives assaulted a chess hall in Hotan , state television reported. Two attackers were killed and another injured after they were subdued by the security forces and people at the scene.
President Xi Jinping presided over a two-day meeting of the Central Work Conference last month, where counterterrorism was reaffirmed as a priority.
"[We must] push forward the domestic and international front lines in fighting terrorism and strengthen anti-terror cooperation with other countries," Xi told senior officials at the meeting, according to state media.
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