A Turkish court has overturned the convictions and released 71 cadets jailed for life for their alleged involvement in a 2016 coup attempt, a lawyer who follows the case closely said Wednesday.

A total of 355 cadets were given life sentences for their alleged attempt to overthrow the government of then prime minister Recep Tayyip Erdogan.

The coup was followed by sweeping purges in which tens of thousands lost their government jobs.

Nearly 5,000 people have been convicted, with nearly 3,000 of them jailed for life.

But human rights lawyers and the cadets' mothers have long argued that the purges ended up jailing people who played no role in the 2016 coup attempt, which claimed some 250 lives.

The Turkish court of cessation overturned 116 of the cadet convictions on Tuesday, releasing 71 of the men and putting the remaining cases on hold pending appeal, said Cemil Cicek, a human right lawyer.

"Their innocence was finally proven, but only six years after their lives were stolen from them," added Omer Faruk Gergerlioglu, an opposition lawmaker who campaigns for human rights.

Turkey accuses US-based Muslim preacher Fethullah Gulen of masterminding the failed coup, a claim he strongly denies.

The aftermath of the coup attempt has transformed every aspect of contemporary Turkish politics, with Erdogan moving to ban opposition parties and his government shutting down independent media.