The Maldivian army has locked down the country's parliament after the opposition vowed to move ahead with a vote against a key ally of President Abdulla Yameen.
Several politicians, however, defied the ban on Monday, fighting off riot police and scaling metre-high walls to enter the parliament compound.
The opposition was hoping to hold a vote to impeach Speaker Abdulla Maseeh, whom they accuse of ignoring allegations of corruption and rights abuses.
They had secured enough support from government defectors to begin impeachment proceedings earlier this month.
The lockdown was ordered to prevent the vote, and Yameen announced that four of the defectors had lost their parliamentary seats.
Ahmed Mahloof, an opposition politician, said soldiers carrying batons followed the members inside on Monday and forcibly ejected them.
"Soldiers in riot gear are dragging elected members out from the parliament," Mahloof told Al Jazeera.
"This is clearly unconstitutional. Many of us have been injured."
Videos posted on social media show soldiers pushing politicians out of the building. A few appear to have been injured.
"There is no better symbol of Yameen's dictatorship than the image of his security forces barring elected MPs from parliament. This president has lost all legitimacy and credibility," said Eva Abdulla, an opposition politician from the Maldivian Democratic Party.
The army could not be reached for comment.
Yameen has arrested or forced into exile most of the opponents who might have challenged him in next year's presidential elections.
Last year, an Al Jazeera investigation revealed how Yameen's government embezzled millions of dollars in tourism revenue.
Yameen denies allegations of corruption and rights abuses.
The embattled president now faces a coalition of four opposition parties, led by his brother Maumoon Abdul Gayoom, who ruled the Maldives with an iron fist for 30 years, and Mohamed Nasheed, the country's first democratically elected president.
Faris Maumoon, Yameen's nephew and the leader of the effort to impeach the speaker, was arrested on charges of bribery last week.
Two other politicians were put on trial on charges of bribery and terrorism.