"We are witnessing a series of arbitrary acts and injustices against immigrants, particularly the persecution of immigrants, as if they were criminals," one of the organizers of the protest, scheduled for 2 pm., told Lusa.

According to Timóteo Macedo, of the Immigrant Solidarity association, the issue is the detention of dozens of immigrants in temporary detention centres, without having committed any crime, but simply because they are listed in the Schengen Information System for having been in another European Union member state before arriving in Portugal.

"This is not a crime at all. The Portuguese state is the one committing illegalities in this regard," he accuses.

In a statement, Solidariedade Imigrante also speaks of a "climate of intimidation against those who work and contribute to this country, who have been in the labour market for several years and in sectors where Portugal has several shortages."

Referring to the changes the government intends to introduce in foreign and nationality laws, the association believes the government "sets a bad example" in terms of reception and integration policies.

"It sets a bad example by not clearly opposing those who threaten to disregard and disrespect the Constitutional Court's recommendations regarding the rollback of the Migration Law and, soon, the Nationality Law," the statement adds.

At the end of July, Solidariedade Imigrante – Association for the Defense of Immigrants' Rights had already organized a protest in Porto, which brought together around a thousand immigrants, according to the organization's figures.

At the time, former Left Bloc MP José Soeiro, who is also a member of the association, reported the detention of 10 immigrants in Temporary Installation Centers in Portugal, a number that, according to Timóteo Macedo, is now around 80 arrests.