Police free Kremlin critic Dmitry Gudkov but keep him as suspect - lawyers

FILE PHOTO: Opposition leader Gennady Gudkov (C, front) takes part in the "March of Millions" protest rally in Moscow, September 15, 2012. Protesters chanting "Russia without Putin" began marching through Moscow on Saturday in a protest seen as a test of the opposition's ability to mount a sustained challenge to President Vladimir Putin. REUTERS/Mikhail Voskresensky

MOSCOW (Reuters) -Police in Moscow released prominent Russian opposition politician Dmitry Gudkov from custody on Thursday, but have kept him as a suspect in a criminal case that prompted his arrest two days ago, his lawyers said.

The 41-year-old former member of parliament was detained on Tuesday amid a crackdown on the Kremlin's political opponents that comes ahead of parliamentary elections in September.