ISTANBUL: Police in Istanbul carried out a dawn raid Wednesday, using tear gas to enter the headquarters of a media company linked to a government critic, enforcing a court order to seize the business just days before a national election.

A prosecutor has ordered Koza-Ipek Holding placed under the management of a trustee while its ties to the movement led by Fethullah Gulen, a US-based moderate Islamic cleric, are investigated. The government accuses the movement of trying to destabilise the state and prosecutors have labeled it a terrorist organization.

The move was part of a broad crackdown on followers of Gulen that has been underway since December 2013 when prosecutors launched a corruption investigation of government ministers and people close to President Recep Tayyip Erdogan. Erdogan alleges that the probes were part of an attempted coup.

Hundreds of police and judiciary officials suspected of ties to Gulen's movement have been dismissed. In May, Turkey's banking regulator seized a bank associated with the movement.

Critics denounced the action as a government crackdown on opposition voices ahead of Sunday's election. Koza-Ipek owns opposition television stations Bugun TV and Kanal Turk, the Bugun and Millet newspapers and other business interests.

The court order was issued late Monday.

Police scuffled with hundreds of Koza-Ipek employees, supporters and opposition legislators before breaking down iron gates and escorting the newly appointed trustees into the building. The melee was broadcast live by Bugun TV and Kanal Turk.

Bugun TV editor Tarik Toros was seen arguing with the trustee manager who entered the station's control room and apparently put an end to the live broadcast.

Outside, protesters chanted "free media cannot be silenced." Some demonstrators were seen being thrown to the ground before being detained, others used umbrellas to shield their faces from police pepper spray. Several people were detained.

Opposition parties denounced the seizure as an unlawful attempt by Erdogan to silence critical media..

"We are faced with an unacceptable incident," said Haluk Koc, a deputy chairman of main opposition the Republican People's Party. "(Erdogan) sees himself as above the law and is busy massacring laws as he sees fit."

US State Department spokesman John Kirby urged Turkey to "uphold universal democratic values ... including due process, freedom of expression and assembly, and of course access to media and information."

EU spokeswoman Catherine Ray said: "We want to reiterate the importance of the respect of the rule of law and media freedom."

There was no immediate government comment.

Akin Ipek, Koza-Ipek's executive board chairman, has denied allegations of financial wrongdoing by the company.

"The group has been audited by independent companies since it was founded. They are lying and trying to slur us," Ipek said in a telephone interview with Bugun TV as police attempted to enter the building.

Journalism groups also condemned the seizure.

The government "is trying to silence every single dissenter days ahead of the election," the Ankara-based Contemporary Journalists' Association said in a statement.

The seizure comes amid more widespread pressure on critical media in Turkey that international watchdogs have called a crisis for the free press. Last month, the headquarters of secular-leaning Turkish daily Hurriyet was vandalised by a mob following verbal attacks on the newspaper by Erdogan.