Could Navalny’s Detention Derail His Movement? Some analysts believe the opposition figure’s arrest could lead to a broader crackdown on his supporters. Alexei Navalny was arrested on his return to Russia. Mstyslav Chernov / EPA / TASS The arrest and detention for thirty days of prominent opposition activist Alexei Navalny is threatening to upend Russian politics in an already fraught year that will include parliamentary elections in September. Since rising to prominence for his anti-Kremlin activism, Navalny — who was poisoned by the nerve agent Novichok in August last year and had been recuperating in Germany until his return to Russia Sunday — has enjoyed only limited popular support. Data from the independent Levada Center pollster, suggests that only 20% of Russians approve of his activities.