Correction: An earlier version of this story inaccurately reported that the pilgrims killed Monday were traveling to Syria. They were coming from Syria.

BAGHDAD--More than 20 people were killed and scores were injured Wednesday in attacks across Iraq, continuing a week of sectarian violence that prompted fears that conflict between religious groups could escalate.

In Babil province, south of Baghdad, 16 people were killed and 46 were injured when a car bomb went off in a busy restaurant Wednesday morning. Police later found the bodies of three members of the Mahdi Army, the paramilitary force of anti-American Shiite cleric Moqtada al-Sadr, in another area of the province, not far away.

In Anbar province — where 22 pilgrims on their way from a shrine in Syria were kidnapped and fatally shot in the desert Monday — two Iraqi soldiers were killed and nine were injured when an explosive charge detonated under a bus close to an Iraqi military base near Ramadi.

Ahmed Abu Risha, the Sunni leader of the Anbar Salvation Council — begun during the war as part of the U.S.-allied Awakening movement — this week blamed such killings on the Sunni insurgent group al-Qaeda in Iraq, saying the attacks were designed to reignite sectarian violence in the country as the U.S. military prepares to depart Dec. 31.

“They want to [cause] sectarian violence again in the country . . . along with the American withdrawal,” he said.

Some religious leaders said the killings could be retribution by Sunni insurgents for Sadr’s recent call to halt attacks on U.S. forces as they continue the drawdown.

Police in Babil said the car bomb detonated about 8:35 a.m. in the restaurant, which is just off the main highway and is a popular spot for soldiers and police officers — frequent targets for insurgents.

A truck driver near the scene said he had just finished loading up his truck with ceramic goods when he heard a terrifying sound.

“At first we thought it was a cooking gas explosion, but as I walked toward the restaurant, the grief and fear overwhelmed me,” said the driver, Ahmad Eshan. “It was an unbelievable sight.”

Among the 16 dead were three children and 11 soldiers. Leaders at local mosques were scrambling for blood donations for the injured, many of whom lost limbs in the attack, said Fadel Abbas, a local police captain.

In Baghdad on Wednesday, two policemen were killed and another was injured when gunmen opened fire on their patrol in the northwestern part of the city.

Special correspondents Uthman al-Mokhtar in Fallujah and Saad Sarhan in Najaf contributed to this report.