The Nauru Government says it has activated off-duty police to secure the tiny Pacific island against the threat of further protests.
The Government accused Opposition MPs of trying to destabilise it by spreading "lies and mistruths" through foreign media, and of trying to score political points over Tuesday's protest outside Parliament.
Numerous police officers were admitted to hospital and two were left with chest injuries, while some of the building's windows were smashed, the Government said.
"It was a blatant criminal act in which 10 police officers were hurt and needed medical treatment," a statement said yesterday.
"The Nauruan Government makes no apology for upholding law and order when its people are in danger and will continue to do everything it can to ensure such violence doesn't happen again."
A spokesman said the Government had ordered extra police on duty.
Mathew Batsiua, one of five MPs suspended from Parliament since last year, was arrested on Tuesday and charged with disrupting the legislature.
He has since been released on strict bail conditions, and the Government denies claims he was entrapped after being offered a meeting with President Baron Waqa.
The hundreds-strong rally was reportedly calling on the Government to resign over corruption allegations aired on broadcaster ABC, new laws cracking down on free speech, and the indefinite suspension of the MPs.
Another suspended MP, Roland Kun, had his passport cancelled on Wednesday after being offloaded from a plane bound for New Zealand via Australia.
"Mr Kun was fleeing the scene of a crime before authorities tracked him down and confiscated his passport," the statement said.
"Mr Kun will have his passport returned if he is found not to have broken the law."
The MP said he was not involved in the protest.
Two other opposition MPs, Squire Jeremiah and former president Sprent Dabwido, are understood to have been arrested on Friday.