A series of blasts hit mainly Shi'ite areas in Baghdad on Thursday, killing at least 17 people in the first wave of attacks on Iraq's capital since a crisis erupted between its Shi'ite-led government and Sunni rivals after the U.S. troop withdrawal.

The apparently coordinated attacks are the first sign of rising violence since Iraq's Shi'ite Prime Minister Nuri al-Maliki moved to sideline Sunni rivals, just a few years after sectarian slaughter drove the country to the edge of civil war.

Two roadside bombs struck Baghdad's southwestern Amil district, killing at least seven people and wounding 21 others, while a car bomb blew up in a Shi'ite neighbourhood in Doura in the south, killing three people and wounding six, security sources said.

More bombs ripped into the central Alawi area, the commercial Karrada neighbourhood, Shaab and Shula in the north -- all are mainly Shi'ite areas.

One roadside bomb killed one and wounded five near the Sunni neighbourhood of Adhamiya, police and witnesses said.

More than 70 were wounded in the blasts.

I saw all the windows were blown out and glass scattered everywhere. The children were scared and crying, said Raghad Khalid, a teacher at a kindergarten near the Karrada blast, where a car bomb blew up near a governmental office.

Some parts of the car bomb are inside our building.

Smoke hung over the blast site in Karrada as ambulances rushed in to ferry the wounded to hospital.

Violence in Iraq has ebbed since the height of sectarian slaughter in 2006-2007 when suicide bombers and hit-squads targeted Sunni and Shi'ite communities in attacks that killed thousands and pushed the country to the brink of civil war.

Thursday's attacks were the first major offensive in Baghdad since November when three bombs exploded in a commercial Baghdad district and another blast hit the city's western outskirts on Saturday, killing at least 13 people.

In October, bomb attacks on a busy commercial street in northeastern Baghdad killed at least 30, with scores wounded.

Iraq is fighting a stubborn insurgency with Sunni Islamists tied to al-Qaeda and Shi'ite militias, who U.S. officials say are backed by Iran, still stage daily attacks.

Days after the withdrawal of the last U.S. troops on Sunday nearly nine years after the invasion that toppled Sunni dictator Saddam Hussein, Iraq's fragile power-sharing government is grappling with its worst turmoil since its formation a year ago.

Shi'ite Maliki is seeking the arrest of Sunni Vice President Tareq al-Hashemi on charges he organised assassinations and bombings, and he wants parliament to fire his Sunni deputy Saleh al-Mutlaq after he likened Maliki to Saddam.

The move against the senior Sunni leaders are stirring sectarian tensions as Sunnis fear the prime minister wants to consolidate Shi'ite control. Iraq's Sunni minority feel marginalised since the rise of the Shi'ite majority in Iraq after the 2003 invasion.

(Additional reporting by Aseel Kami; Writing by Patrick Markey and Rania El Gamal; Editing by Michael Roddy)