About 500 political opposition supporters in Kyrgyzstan have protested in front of the State Committee for National Security headquarters (GKNB) in Bishkek, where opposition leader Omurbek Tekebaev was being held as part of what authorities describe as a criminal corruption investigation.
The demonstrators – including former President Roza Otunbaeva and several opposition lawmakers -- demanded Tekebaev's immediate release from custody.
They say authorities are "politically persecuting" opposition figures from Tekebaev's opposition Ata-Meken (Fatherland) party and other members of Kyrgyzstan's 2010 interim government, which was briefly in power after the Kyrgyz Revolution of April 2010.
The demonstrators dispersed late on February 26 after a vigil that went into the night, vowing they would return on February 27 to continue their protest.
Tekebaev, a parliamentary deputy who leads the Ata-Meken party and its parliamentary faction, was detained by plainclothes police at about 3 a.m. local time on February 26 when he arrived at Bishkek International Airport.
He had been traveling abroad to attend the Parliamentary Assembly of the Organization for Security and Cooperation in Vienna.
The prosecutor's office in Bishkek said Tekebaev would be held for up to 48 hours for questioning as part of a criminal investigation launched against the Ata-Meken party.
Tekebaev is the third member of Ata-Meken to be detained by authorities for questioning in recent weeks as part of the alleged corruption probe.
Earlier in February, authorities also detained parliamentary deputies Almabet Shykmamatov and Aida Salyanova for questioning.
The detentions come despite the fact that Tekebaev, Shykmamatov, and Salyanova all have parliamentary immunity from prosecution.
So far, no formal charges have been filed against them.
Supporters of Kyrgyz Omurbek Tekebaev demonstrate against his arrest in Bishkek on February 26
The 58-year-old Tekebaev was once an ally of President Almazbek Atambaev.
But Tekebaev became a leading political opponent of Atambaev during the summer of 2016 after Kyrgyzstan's president proposed a series of constitutional amendments that could cement a long-term hold on power for Atambaev and his allies in the Central Asian state.
Since then, the amendments have been pushed through parliament and adopted by Atambaev's political allies.
Although Atambaev's presidential term ends in 2017 and he cannot run for reelection, critics say the recent constitutional amendments would allow the president's allies to maintain power after his term ends.
The amendments significantly boosted the powers of the prime minister, prompting speculation that Atambaev could either position himself to become the next prime minister or install a loyal political ally in the role.
Tekebaev and his party had strongly opposed the constitutional amendments.
Tekebaev also has called for Atambaev to be impeached and has demanded that authorities investigate the president and his family members for evidence of corruption.
Kyrgyzstan's next presidential election is scheduled for November 19.
If Tekebaev is stripped of his parliamentary immunity by parliament and criminal charges are filed against him, it could prevent him from running as a presidential candidate.
'Retribution' For Revelations
Former Kyrgyz lawmaker Asiya Sasykbaeva, a member of the Ata-Meken party, said during the February 26 protest rally at the GKNB headquarters in Bishkek that she believes authorities are trying to prevent Tekebaev from running for the presidency.
"It is fully possible that they will now fabricate some criminal case, because I have just been told that he had been detained under Article 303" of Kyrgyzstan's Criminal Code, Sasykbaeva said. The article in question deals with the crime of corruption.
"We think that the far-reaching plans of the current authorities are most likely related to the upcoming presidential election," Sasykbaeva said.
She also alleged that Tekebaev was facing retribution from authorities in Bishkek "for disclosing major fraud schemes, including ones involving President Atambaev's inner circle."
Prosecutors on February 26 said the allegations against Tekebaev stem from the time he was deputy prime minister in the interim government that followed the Kyrgyz Revolution of 2010.
They allege, among other things, that Tekebaev demanded $1 million from Russian businessman Leonid Mayevsky in exchange for allowing him to serve on the board of Alfa Telecom – a telecom firm that had been partially nationalized by the new government.
Tekebaev has denied the allegations.
In a February 26 statement, the prosecutors alleged that Tekebaev "did not carry out his obligations and refused to return the money."
They said he "instead threatened physical harm in the event of any further demands or information being released to the public about the situation."
Upon news of Tekebaev's detention in Bishkek, about 50 people gathered in the southern city of Osh on February 26 to protest.
His supporters also gathered early on February 26 for a protest near Bishkek’s airport, where several people were detained and released the same day.
Those detained included Ata-Meken lawmaker Kanybek Imanaliev and RFE/RL Kyrgyz Service correspondent Ulan Egizbaev.
With reporting by RFE/RL Krygyz Service correspondent Ulan Egizbaev in Bishkek and Reuters