Iraqi authorities tightened security in the capital Baghdad on Saturday, one day after protesters demanding reforms breached the city's heavily fortified Green Zone.
Security forces closed two major bridges and roads leading to the area, which houses parliament, government offices and foreign embassies in central Baghdad.
"Security measures have also been bolstered around the Green Zone and government buildings," a police official told dpa without giving details.
Anti-government protesters were absent from the area and major squares in Baghdad on Saturday.
On Friday, thousands of angry demonstrators stormed the area and briefly occupied the premier's office there.
Some protesters said security troops opened fire, killing at least three of them and injuring 22 others.
The government denied the accusation and imposed a curfew in Baghdad that was lifted late Friday.
Prime Minister Haider al-Abadi accused what he called "infiltrators" of seeking to foment chaos in Iraq, which is engaged in a US-backed fight against the Islamic State extremist militia.
Friday's breach of the Green Zone was the second in less than a month.
Iraq has for months been locked in a crisis over forming a government of independents. Major political blocs in parliament have repeatedly blocked the move.
Iraqi governments have been formed along political and sectarian lines since the US-led 2003 invasion that deposed Saddam Hussein - a system that critics say contributes to corruption and administrative incompetence.
Al-Abadi, a Shiite Muslim, has warned that the current row is to the advantage of the Islamic State radical Sunni organization that holds key areas in Iraq.