Ammar Al Shamary

Special for USA TODAY

BALAD, Iraq — Iraqis on Friday mourned the victims of yet another terror attack, and some said they won't let the Islamic State ignite a new conflict between Sunni and Shiite Muslims.

At least 37 people were killed and more than 62 wounded when suicide bombers and gunmen attacked a Shiite shrine in this town, 50 miles north of Baghdad, Iraqi police said.

Islamic State militants, who are Sunnis, "are trying to bring us back to the sectarian era" in 2006-07, said Mahmoud Salim, 42, a shopkeeper who witnessed the assault. “They are hitting religious place to arouse the anger of Shiites and Sunnis again. But they will fail.”

Salim was at the Sayyid Mohammed shrine when the terrorists struck. The Islamic State, which claimed responsibility for the attack, considers Shiites to be apostates.

Police said the attack started Thursday night with mortar fire, then a suicide bomber blew himself up in the midst of policemen at the entrance, the Associated Press reported. A second bomber and nine gunmen entered the shrine and attacked security forces and civilians. A third bomber was killed before he detonated his explosives, police told the AP.

People had gathered at the shrine for the Muslim holiday of Eid al-Fitr, which marks the end of the holy month of Ramadan.

"The shrine was very busy,” said Salim. “People usually come to visit the shrine and spend some time in the market during Eid. There is no other activity can be done in the city.”

The attack follows a horrific suicide bombing in a crowded shopping district in Baghdad on Sunday that killed at least 186 people, the worst single bombing in Iraq since the U.S. invaded the country in 2003. The Islamic State claimed responsibility for that attack, too.

Many Iraqis are fed up with the central government’s failure to stop a string of terrorist bombings by the Islamic State in recent months, as Iraqi forces have gradually driven the militants out of cities they seized in 2014. Last month, Iraqi forces liberated Fallujah, about 40 miles west of Baghdad, and are now focusing on retaking Mosul, the country's second largest city.

In response to the latest incident, Prime Minister Haider al-Abadi fired Baghdad’s security chief on Friday, the AP reported.

Abo Layan Al Timimi, 38, a teacher who lost his uncle and cousin in the attack, said the militants encircled Balad in 2014 but never managed to conquer it despite a six-month-long siege. "I can't imagine after that how we thought the threat was over,” he said.

A distraught Al Timimi said his deceased relatives had young children. "They left little kids behind,” he said. “Who will look after them? Who can help them?"

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