Insurgents unleashed a new wave of attacks on Tuesday in Iraq, killing at least 49 people, officials said, the latest in a surge in violence across the country that has raised concerns over a return to sectarian bloodshed. Also, seven militants were killed.

There was no claim of responsibility for the attacks, mostly car bombs in Shiite areas. Al-Qaida's Iraq branch, which has been gaining strength in recent months, frequently targets Shiites, security forces and civil servants in an effort to undermine the Shiite-led government in Baghdad.

Iraq is weathering its deadliest outburst of violence since 2008, with more than 2,000 people killed since the start of April. The bloodshed appears to be largely the work of resurgent Sunni militants such as al-Qaida, feeding off Sunni discontent with the Shiite-led government.

Violence increased sharply in April and May, with frequent bombings in civilian areas raising concerns that a widespread sectarian conflict might once again break out in Iraq. The bloodshed accelerated after a deadly April 23 crackdown by security forces on a Sunni protest in the northern town of Hawija against the Shiite-led government.

In Baghdad's northern Shaab neighborhood, two parked car bombs targeted car dealers and a commercial area, killing nine people, including a policeman, a police officer said. He said 24 others were wounded.

In the Shula neighborhood, a bomb exploded in an open-air market in, followed by a second blast after rescuers rushed to the scene, killing 10 civilians and two policemen, a police officer said. Twenty-seven people were wounded.

Five civilians were killed and 16 wounded in a car bomb explosion in a market in Baghdad's eastern suburb of Kamaliya. A car bomb ripped through a commercial area in the capital's southern Dora neighborhood, killing four and wounding 15, police said.

In the predominantly Sunni neighborhood of Amiriyah, two civilians were killed and 12 wounded in a car bomb explosion in a commercial area. Three others were killed and 13 wounded in another car bomb explosion in the northern Hurriyah neighborhood.

Also Tuesday, clashes erupted at dawn between security forces and militants in Baaj, a remote northwestern town near the Syrian border, and left four policemen dead and five wounded. Police said seven militants were killed.

In another attack, a government-allied, anti-al-Qaida Sunni militiaman was killed and two others wounded when a bomb attached to their car exploded in the western Baghdad suburb of Abu Ghraib, police said. The pro-government militiamen, or Sahwa, joined with U.S. troops to fight al-Qaida before the U.S. pullout in late 2011. Since then, they have been a frequent target for al-Qaida in Iraq, which considers them traitors.

Also in Abu Ghraib, a car bomb killed three civilians and wounded six others.

Elsewhere in Baghdad, a barber was gunned down by gunmen in a speeding car, and a physician was killed by a bomb attached to his car.

Outside the city of Baqouba, about 60 kilometers (35 miles) northeast of Baghdad, a suicide bomber blew himself up inside a tent where a funeral was taking place, killing four and wounding 17 others, Provincial councilman Sadiq al-Husseini said. Police could not say whether the targeted funeral was for a Shiite or Sunni family.

In the oil-rich city of Basra in southern Iraq, two car bombs exploded outside a hotel which hosts mainly foreign investors, wounding three Iraqi civilians, police said. The explosion shattered the windows of the hotel, and foreigners were seen leaving it in armored vehicles. Basra is 550 kilometers (340 miles) southeast of Baghdad.

Five medical officials confirmed casualty figures. All spoke on condition of anonymity as they were not authorized to release information to reporters.

At least 40 people were killed the day before in Iraq. According to the United Nations mission to Iraq, last month's violence claimed the lives of 761 Iraqis and wounded 1,771 others. (AP)