Kazakhstan’s Bureau for Human Rights and Rule of Law and Human Rights Charter Foundation in their joint statement on June 11 protested what they called "mass violations of civil rights and freedoms, namely freedom of expression and freedom of assembly."

Police on June 9 detained hundreds of demonstrators who were calling the election illegitimate, and hundreds more the following day when protesters challenged officially announced preliminary results of the poll giving an overwhelming victory to interim President Qasym-Zhomart Toqaev, who was handpicked by former authoritarian President Nursultan Nazarbaev to be his successor.

The joint statement by rights groups says police used "unnecessarily excessive violence against protesters" in the capital, Nur-Sultan, the country's largest city, Almaty, and other towns and cities and kept many of them for up to 10 hours without food, water, and contacts with their relatives, which can be defined as "a violent attitude."

According to the statement, during the night of June 9-10, hundreds of people went through administrative hearings by courts without their lawyers being present, which is also a violation of their rights.

The statement also says that the whereabouts of many detained people remain unknown and urges the authorities to immediately inform relatives about their location.

The statement by the rights groups came hours after Kazakhstan's Central Election Commission (CEC) announced the poll's final results, confirming Toqaev's victory.

The CEC said on June 11 that Toqaev took 70.96 percent of the ballots in the vote. Former journalist Amirzhan Qosanov was a distant second in the balloting with 16.23 percent.

Reports early on June 11 said police were arresting demonstrators in some districts of the country's largest city, Almaty, after hundreds of people gathered to protest the official results.

Video posted on social media from Almaty overnight showed dozens of people running in the streets and being pursued by a special police unit.

The arrests in the early morning hours came after more than 100 protesters had gathered outside a police building in Almaty late on June 10 to demand the release of a popular folk singer named Rinat Zaitov.

Zaitov was among dozens of demonstrators arrested earlier on June 10 after gathering in the center of Almaty to protest the official results of the election, which international observers said was "tarnished" by "clear violations of fundamental freedoms."

Zaitov was eventually released and asked the demonstrators to return to their homes shortly before the arrests began.

Toqaev's landslide victory was widely expected after he received the blessing of Nazarbaev, who officially stepped down as president in March after ruling Kazakhstan for nearly 30 years.

Nazarbaev continues to hold many important political positions and still wields considerable power within the country and inside his political party, Nur-Otan, whose presidential candidate was Toqaev.

Monitors from the Organization for Security and Cooperation in Europe (OSCE) said in a statement that "a lack of regard for fundamental rights, including detentions of peaceful protesters, and widespread voting irregularities on election day, showed scant respect for democratic standards."

"While there were seven candidates, including for the first time a woman, the election showed that there is a need for genuine democratic consolidation and significant political, social and legal reforms," said George Tsereteli, special coordinator and leader of the OSCE short-term observer mission.

Deputy Interior Minister Marat Qozhaev called hundreds of demonstrators detained in Nur-Sultan, Almaty and other towns and cities "radically-minded elements."

Security measures have been heavily stepped up in Nur-Sultan and Almaty.

Internet access in the two cities was reported to be extremely slow, preventing live streaming and making it very difficult to read social-media sites.

Meanwhile, Qosanov, who positioned himself as an opposition candidate, said on June 10 that he planned to set up a new political party ahead of parliamentary elections next year.

Addressing his supporters in Astana, he said he considered his presidential bid a success, claiming that it helped "legitimize" the opposition.

However, some of those attending the meeting called Qosanov "a politically dead person" and "a puppet candidate" because he conceded defeat before the official election results were made public.

He was also criticized for posting a video statement on Facebook late on June 9 in which he called the anti-government rallies a "real political provocation" by supporters of "pseudo-opposition figures" based abroad.

None of the elections held in Kazakhstan since it became independent in 1991 has been deemed free or fair by international organizations.

Many activists were detained and given fines or jail sentences in the run-up to the election, while some young male activists were suddenly drafted into the army.

With reporting by Reuters, TASS, and Kazinform