Six men have been sentenced to death in the first convictions after mobs of Muslim Uighurs rampaged through a western city in July, leaving nearly 200 people dead in the deadliest riot in China for decades.

Among those found guilty was a man convicted of stabbing or bludgeoning to death five people on the night of July 5 and a second who was part of a mob that killed a family of five Han Chinese as they cowered in their grocery shop.

Officials say that 197 people died and 1,700 were injured during the violence in Urumqi, which was started by Uighurs resentful of Beijing rule and an influx of Han Chinese to the region.

The Urumqi Intermediate People’s Court put the seven men on trial this morning for their roles in the riot. The trials, in three courtrooms, resulted in convictions of all.

The seventh was jailed for life, a show of leniency after he co-operated with investigators and helped to lead police to another man who joined him in the night of killing, the court said. The seven men were found guilty of murder, arson and robbery. Death sentences in China are either by lethal injection or by firing squad.

Abdukerim Abduwayit used a dagger and a pipe wrench to kill five people, the court said. He also set fire to a building in the centre of the city, forcing 13 people to jump off to escape and causing more than 260,000 yen (£26,000) of damage.

In the second case, Gheni Yusup led Abdulla Mettohti, Adil Rozi and Nureli Wuxiu’er in beating four people to death and injuring another.

Abdullah Mettohti then joined another group in attacking a grocery store selling grain and oil to residents of a district with a mixed population of Uighurs and Han. The Han Chinese owner, his mother, wife, 14-year-old son and 27-year-old nephew were trapped inside as the attackers rushed in.

Witnesses told The Times that they watched from an apartment building across the street as members of the family tried to run to safety in the street only to be dragged back and killed. The teenager took refuge in the family chicken coop but was found and beheaded. The attackers then set fire to the store. The wife was later identified by DNA testing, family members said.

A nephew of the wife told The Times: “Members of our family were in court today. We are very pleased with this verdict. We hope this is the first step to bringing all these criminals to punishment.”

The third case involved Alim Metyusup and Tayirejan Abulimit, who killed three people and seriously injured one. Alim was also convicted of murdering two other people. Tayirejan Abulimit was given a life sentence because he turned in his fellow attacker, the court said.

The sentences came just three days after a court in southern China sentenced a man to death for his role in a brawl at a toy factory in which two Uighur men were killed. Those deaths sparked the fury that transformed the capital of the far western Xinjiang region into a killing field where Uighurs chased down Han Chinese in the street, pulled drivers out of their cars, set fire to buses and hacked dozens of people to death in a night of violence.

Police lost control after they tried to break up a peaceful demonstration by students calling for an investigation into the fight at the toy factory. Paramilitary police poured into Urumqi to restore order. Within a day they had carried out sweeps across Uighur districts, taking away hundreds – if not thousands – of men for investigation.

The riot was the worst ethnic violence in China for decades and highlighted simmering resentment among ill-educated Uighurs angered at seeing jobs go to Han who have moved to the region from poor central provinces. Uighurs, many unable to speak Mandarin Chinese, have difficulty competing even for manual work against the Han and eke out a living in crowded slums and tenement blocks.

Times Recommends

• 'New York has lost its edge'
• Copenhagen will fail – and quite right too
• More than 17,000 new underwater species found