Thousands of Basque separatist sympathizers have held a rally in northern Spain celebrating the release from jail of a prominent regional leader four days after he completed a more than six-year sentence for trying to resurrect the banned political wing of armed group ETA.

Arnaldo Otegi, who was considered the political leader of the pro-Basque independence movement before his 2009 imprisonment, was greeted by more than 8,000 supporters at the Anoeta cycling arena in the city of San Sebastian.

He entered the venue flanked by traditional regional folkloric dancers and is expected to address his followers there late Saturday.

There has been speculation that Otegi might present himself as a candidate for regional president in local elections later this year, although his sentence bans him from holding office until 2021.