Khabarovsk (Russia) (AFP) - Thousands of people braved the rain in the far-eastern city of Khabarovsk on Saturday to attend another huge protest march against the arrest of the region's popular governor.

For a fourth weekend, demonstrators marched through the streets chanting anti-Kremlin slogans and in support of ex-governor Sergei Furgal, who was arrested and taken to Moscow last month to face charges of masterminding murders 15 years ago.

The arrest of the 50-year-old -- who was elected in 2018, beating a rival from the majority United Russia party -- has sparked unprecedented protests in the far-eastern region.

Locals see the move as politically motivated and question why he is being tried in the far-away capital.

"To grab the governor like that, like the worst bandit... that's spitting into the faces of the citizens who elected him," 40-year-old Stanislav Nasonov told AFP at the rally.

Furgal, held in Moscow's notorious Lefortovo prison, has been fired, and President Vladimir Putin has replaced him with a new young governor with no ties to the region in a move that has not gone down well in Khabarovsk.

The protest movement against the government is the largest outside of Moscow in several years.

The rally on Saturday was visibly smaller than the previous weekend, which was the largest over 22 days of near daily protests. 

Journalists estimated turnout at around 30,000 people while the Khabarovsk city hall put the number at just 3,500, claiming there was "falling interest". 

Last week, the Kremlin said the protests were fuelled by opposition activists from outside the region.

'No trust'

Despite a downpour, spirits were high among the marchers on Saturday, who clapped, waved signs and Russian flags and chanted "20 years -- no trust" in reference to the time Vladimir Putin has spent in power.

"Our freedom of choice is being taken away," said pensioner Pyotr Smirnov, 65. "We are protesting to open that window again, and not just for us but for the whole of Russia."

Smaller protests were also held in several cities across the country, most of which ended with arrests.

There were 55 people arrested at demonstrations throughout Russia held in support of Khabarovsk, according to OVD-Info group which tracks arrests at rallies. 

At protests ranging from a few dozen people to several hundred, 21 people were arrested in Saint Petersburg, 13 in Moscow and five in Vladivostok, another major city in the Far East.

Investigators say Furgal organised the murders of several businessmen in the Far East in 2004 and 2005.

Russia's Investigative Committee, which probes major crimes, said last month that it had "irrefutable evidence" of Furgal's involvement.

Furgal has pleaded not guilty to the charges against him.

The July 9 arrest of the former doctor came just days after Putin -- who has been in power for two decades -- won a landslide ballot on constitutional reforms that could allow him to extend his rule until 2036.