Bombings in and around Baghdad killed at least 21 people and wounded over 100 on Thursday, health and security sources said, the latest attacks in a bloody month that have stoked fears Iraq could return to broad sectarian fighting.

Tensions have been high in the country since the last U.S. troops left in December, with ongoing political crises between Iraq's main Shi'ite, Sunni and Kurdish factions further aggravating concerns.

In the deadliest incident, at least eight people were killed and 30 wounded when a bomb in a parked taxi exploded at the entrance of a Baghdad market in the mainly Shi'ite Muslim district of Washash, police said.

"There were bodies scattered everywhere. Glass and vegetables covered the whole place," said police officer Ahmed Nouri, who was on patrol nearby when the bomb detonated.

"I feel like my clothes are completely covered in blood and the smell of it is in my nose," he said.

Most of the victims were vendors setting up their produce in the early hours before shoppers arrived, he said.

"In some places you cannot tell the blood from the (pulverized) vegetables," Nouri said.

Violence in Iraq has fallen since the peak of sectarian fighting in 2006-07 following the 2003 U.S.-led invasion but insurgents remain capable of lethal attacks.

Almost 200 people have been killed so far in June across the country in a rise in attacks targeting mainly Shi'ite pilgrims and shrines.

The worst incident occurred on June 13 when bombers targeted Shi'ite pilgrims, killing more than 70 people in one of the bloodiest days since U.S. forces withdrew.

POLITICAL TENSIONS

Opponents of Iraqi Prime Minister Nuri al-Maliki accuse him of trying to consolidate power at their expense.

The Shi'ite leader is fending off attempts by Sunni, Kurdish and some Shi'ite rivals to organize a vote of no confidence against him.

Maliki said on Wednesday he will call for early elections if other political parties refuse to negotiate to break a deadlock over power-sharing that threatens to stoke sectarian tensions even more.

In the central Iraqi city of Baqubua, at least six people were killed and 51 others wounded late on Thursday when a bomb concealed in a parked car exploded near shops and cafes in a mainly Shi'ite area, security and health sources said.

"The rescue teams are still trying to retrieve corpses from underneath the debris," a source in Diyala health directorate said.

Baquba is the capital of Diyala province, a fertile agricultural area which has long been one of the most volatile regions, inhabited by a mix of Sunnis, Shi'ites and Kurds.

A separate car bomb attack in Taji, a town 20 km (12 miles) north of the capital, killed four and wounded 20 early on Thursday, police said.

The bomb in the mainly Sunni town was targeting a government building, which was severely damaged.

Another roadside bomb targeting a police patrol killed one and wounded five in Abu Dsheer, a Shi'ite area in southern Baghdad, police said.

Bombers also struck Falluja in the Sunni Muslim province of Anbar, 50 km (32 miles) west of Baghdad on Thursday.

A suicide bomber killed two police officers and wounded four others after an attack targeting a government compound, police said.

They also reported that three more police officers had suffered injuries in a separate attack to the south of the city when a bomb in a parked car blew up.