MOSCOW (AP) — Russian opposition leader Alexei Navalny has been released after spending a month in jail for calling for an unsanctioned protest.

Navalny walked free on Friday and vowed to keep protesting against the Russian government.

Navalny, along with several opposition activists, have led a protest movement earlier this summer against Russian election authorities' decision to bar nearly two dozen independent candidates from running for the Moscow city legislature in the Sept. 8 election. One of these rallies was the largest anti-government protest that Moscow had seen in eight years.

Authorities have clamped down on the protests, refusing to give permission for them, briefly detaining 1,400 people and arresting dozens of protest leaders, including Navalny. Some of the independent city council candidates were sentenced to several back-to-back short stints in jail.