Police in Barcelona said some 315,000 people gathered in Catalonia's capital on Sunday to demand the release and freedom to return for a number of Catalan politicians who had been involved in the failed attempt to break away from the rest of Spain last year. Organizers said the turnout was much higher.

Read more: Catalan independence — What you need to know

The rally comes six months after pro-independence activists Jordi Cuixart and Jordi Sanchez, who has been put forward by lawmakers as the regional presidential candidate, were imprisoned. Both men face rebellion charges which could lead to jail terms of 30 years.

The demonstrators were united in their protest against the pre-trial imprisonment of the political leaders.

The presidents of the National Catalan Assembly (ANC) and Omnium Cultural, a Catalan cultural association that presses for Catalonia's self-determination, are among the separatists awaiting trial. It was these two groups which organized Sunday's demonstration under the umbrella "Space for Democracy and Co-existence." They had the support of trade unions, parents' associations, actors' associations and youth groups. Not all of them are in full support of secession for Catalonia but they object to the detentions and want talks between Catalonia and Madrid to resolve the current impasse.

"The majority of Catalans, regardless of their political position, agree that pre-trial jail is not justified," said regional UGT union leader Camil Ros. "What we as labor unions are asking for now is dialogue."

Police said 315,000 people attended the rally with hundreds of buses bringing protesters in from other areas.

Impasse ahead of more elections

Nine separatists are in prison awaiting trial for their part in the political process for independence, declared illegal by Madrid. Former President Carles Puigdemont is awaiting a decision in Germany on extradition while six others are abroad saying they fear arrest if they return to Spain.

Former President Carles Puigdemont is awaiting a decision on his extradition from Germany.

Direct rule by Spain's central government in Madrid has been imposed on Catalonia since its unilateral declaration of independence in October. Jordi Sanchez was among those elected in the December elections in Catalonia, which saw a renewed, if slight, majority for the separatists. Although Sanchez was proposed as candidate to lead the new Catalan regional government, a judge has refused to allow him out of jail to be sworn in.

If a new leader is not elected in Catalonia by May 22, new regional elections will be held.

jm/tj (EFE, AP, AFP)

Each evening at 1830 UTC, DW's editors send out a selection of the day's hard news and quality feature journalism. You can sign up to receive it directly here.