(CNN) -- At least 18 people were killed Sunday in a wave of bombings in Iraq, making it the country's deadliest day in nearly a month.
The country's majority Shiite Muslim community seemed to be the main target of the attacks, with a Shiite shrine among the targets.
The blasts seem to be part of a new increase in the level of violence in the country after a period of relative stability.
There were six explosions in and around Baghdad, which killed 13 people, police officials in the capital said. At least 21 other people were wounded in the blasts in the city center, the Baghdad neighborhoods of al-Mashahda and al-Amel, and the nearby city of Taji.
A car bomb later exploded near a Shiite shrine in al-Madaan, killing two people. Nine other people were wounded, including four Iranians, police officials told CNN. Iraq is the site of many Shiite holy sites visited by pilgrims from Iran.
The shrine is about 20 kilometers (12 miles) southeast of Baghdad.
And in the predominantly Shiite city of Kut, three Iraqi police officers were killed and four people were wounded in a car bomb explosion at a police checkpoint.
The incident occurred Sunday around 7 a.m. about 110 kilometers (68 miles) south of Baghdad in Wasit province.
Health and police officials in Kut told CNN earlier that eight people were killed and 18 others wounded in that bombing, but the Interior Ministry then said some of those casualties were from a car accident.
Three weeks ago, at least 63 people were killed and roughly 200 others wounded in a fresh wave of violence largely targeting Iraqi security forces and predominantly Shiite areas, government officials said.
The September 9 blasts and shootings across Iraq came on the heels of a particularly brutal few recent weeks in the Middle Eastern nation. More than 70 Iraqi security force members, for instance, were killed in August, according to the Interior Ministry.
Iraq has battled political infighting among Shiites, Sunnis and Kurds, raising worries that the political conflict will return to the level of violence that nearly tore the country apart in 2006.
While violence has decreased since the height of the U.S.-led war in 2005 and 2006, there has been a sharp escalation in attacks in recent months. In July, the number of dead hit a two-year peak with 325 deaths reported, according to the Interior Ministry. That's the deadliest single month since August 2010, it said.
Baghdad's Shiite-dominated government has blamed the recent attacks on Sunni insurgents with ties to al Qaeda.
U.S. troops completed their withdrawal from Iraq in December.