Police in Kazakhstan have arrested hundreds of people protesting against a poll to elect the country's first new president in 30 years.

The election was called after long-time leader, 78-year-old Nursultan Nazarbayev, stepped down in March.

Large-scale protests - the biggest the country has seen in years - have been reported in Kazakhstan's capital, Nur-Sultan, and its largest city Almaty.

Hundreds of demonstrators, and several journalists and activists monitoring them, were reportedly detained by police.

Deputy Interior Minister Marat Kozhayev told a briefing at the central election commission that 500 people had been arrested at “unsanctioned rallies,” according to informburo.kz.  

He described the protesters as “radical elements seeking to destabilize society.”

“People took to the streets at the call of the banned opposition group, the Democratic Choice of Kazakhstan,” Kozhayev was quoted as saying by informburo.kz.

According to the BBC, Mukhtar Ablyazov, leader of the Democratic Choice of Kazakhstan, said the election was a sham with a predetermined outcome and urged his supporters to take to the streets in protest.

Mr. Tokayev, who cast his ballot in the capital, has urged police to exercise restraint.  He told the BBC his government would be tolerant towards those with different views.

Exit polls suggest 66-year-old Mr. Tokayev, a former director-general of the United Nations Office in Geneva, won the election with 70% of the vote.