A Turkish court has released the journalist and novelist Ahmet Altan after more than four years in prison on charges of involvement in a failed 2016 coup attempt, charges he had always denied.

The court of cassation ruling came a day after the European court of human rights (ECHR) demanded the 71-year-old’s freedom in a verdict that accused Turkey of violating his civil rights.

“I don’t know how I got out. I was sitting [in prison] and all of a sudden I was told this evening that I would be released,” Altan said at his home in Istanbul. “I just saw my children. I will now spend some time with them.”

The award-winning novelist and newspaper editor was jailed after writing politically sensitive pieces critical of the president, Recep Tayyip Erdoğan, and in support of Kurdish rights.

Altan was arrested during purges that followed the coup attempt and accused of backing the uprising by “disseminating subliminal messages to the public”.

He was subsequently sentenced to life imprisonment for trying to overthrow the government – a ruling later quashed by Turkey’s top court. When the case was re-examined, he was sentenced to 10 years and six months for “knowingly supporting a terrorist organisation” that was involved in the coup bid.

“Very happy to hear Turkey’s court of cassation has just ordered the release of novelist Ahmet Altan after more than 4.5 years in jail,” the European Parliament’s Turkey rapporteur, Nacho Sanchez Amor, tweeted.

“Will be even happier after seeing him enjoying fully his freedom and all charges dropped. Hope all other [ECHR] rulings will be applied too.”

Very happy to hear #Turkey's Court of Cassation has just ordered the release of novelist #AhmetAltan after more than 4,5 years in jail! Will be even happier after seeing him enjoying fully his freedom and all charges dropped. Hope all other @ECHR_CEDH rulings will be applied too.

— Nacho Sánchez Amor (@NachoSAmor) April 14, 2021

The ruling came as Erdoğan mounts a charm offensive aimed at mending torn relations with the European Union and building a new rapport with Joe Biden’s US administration.

EU leaders highlighted Turkey’s deteriorating human rights record during a summit in Ankara last week. Biden’s White House has also made human rights a much bigger issue in US-Turkish relations than it had been under the administration of Donald Trump.

Turkish officials argue that the courts are independent and not swayed by politics or Erdogan’s whims. But critics accuse Erdoğan of stacking them with supporters after sacking or jailing tens of thousands of people in various government posts.

Western observers have been watching Altan’s case and some other renowned prisoners for signs of Turkey’s diplomatic intentions and future political course.

The best-known case involves civil society leader Osman Kavala, who has been in custody without a conviction for nearly four years. He was briefly freed and cleared of all charges before being almost immediately rearrested in 2019.

The court of cassation ruling on Wednesday overturned his conviction in the 2019 case related to charges of “assisting a terrorist organisation”. He had turned to the ECHR for help in 2017 after calling the charges against him “grotesque”.

The Strasbourg-based rights court on Tuesday found “no evidence that the actions of the applicant had been part of a plan to overthrow the government”. It ordered Turkey to release him immediately and pay him €16,000 in damages for violating his rights to freedom of expression.

“Deprivation of liberty, in particular continued detention, must be based on reasonable suspicion,” the ECHR ruling said.

The ruling “found that the applicant’s criticisms of the president’s political approach could not be seen as an indication that he had had prior knowledge of the attempted coup”.