Algeria claims strikes exploited by 'subversive' plots
"An exploitation of trade union activity by certain subversive movements aimed at sowing sedition has recently been noted," a statement from the office of Prime Minister Abdelaziz Djerad read.
The interior ministry had described the firefighters' demonstration as a "plot" encouraged by "parties hostile to Algeria", a recurring accusation against any dissenting voice.
Earlier this week, influential army magazine El Djeich warned against "fomented and suspicious strikes", noting that "national security is a red line" ahead of legislative elections on June 12.
The magazine said strikes could "only be part of an attempt to stir up trouble" rather than boost workers' rights.
Algeria's government is seeking to calm anger with unemployment at 15 percent, soaring prices and shortages of basic food items.
The deep economic crisis has been exacerbated by the fall in oil revenues and political deadlock since the popular Hirak pro-democracy uprising began two years ago.
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The Hirak protest movement was sparked over president Abdelaziz Bouteflika's bid for a fifth term in office.
The ailing autocrat was forced to step down weeks later, but the Hirak has continued its demonstrations, demanding a sweeping overhaul of a ruling system in place since Algeria's independence from France in 1962.
Authorities say the Hirak movement is being infiltrated by those who want to drag it towards violence. The Hirak has called for a boycott of the polls.
Agencies contributed to this report.