A spate of attacks that killed 60 people in Iraq overshadowed preparations to mark the end of the holy month of Ramadan on Friday, amid warnings insurgents would look to carry out further deadly strikes.

The violence, the worst in more than three weeks, hit 15 cities across the country and left more than 250 people wounded on Thursday, just days before the Eid festival that is set to begin on Sunday.

The attacks brought the number of dead nationwide over the course of Ramadan, which began on July 18, to 382, according to an AFP tally. There has been at least one bombing or shooting on every day of the holy month but one.

Thursday's deadliest violence struck in and around Baghdad, where 32 people were killed in a series of attacks throughout the day, while blasts and shootings also took place in the south, west and north of Iraq.

Twin roadside bombs outside an ice cream cafe in the east Baghdad neighbourhood of Zafraniyah detonated late Thursday evening, killing four people and wounding 23, security and medical officials said.

Also in the evening, an explosion in Sadr City, in the capital's north, killed 11 and left 46 hurt, while a morning car bomb in Husseiniyah, north Baghdad, killed six and wounded 32.

All three neighbourhoods are predominantly Shiite.

Meanwhile, gunmen armed with silenced weapons opened fire on a checkpoint in the town of Massud, on Baghdad's northern outskirts, killing 10 soldiers and wounding 10, according to security and medical officials.

Also Thursday, a car bomb in the town of Taji, just outside the capital, left one dead and six hurt.

There were also attacks in Tal Afar, Mosul, Kirkuk, Daquq, Dibis, Kut, Al-Garma, Al-Baaj, Badush, Tuz Khurmatu, Khales and Baquba.

A series of attacks in Kirkuk province, north of Baghdad, killed nine people.

In the town of Daquq, a suicide attacker blew himself up at an anti-terrorism department's compound, while in the province's eponymous capital, at least four car bombs were set off across the city -- including two at the offices of the state-owned North Oil Company.

"I came to investigate one of the attacks near the company compound," said police Colonel Abdullah Kadhim, head of Kirkuk city's sniffer dog unit.

"Suddenly, another bomb went off near me, and it damaged lots of cars and company property inside the parking lot."

Kadhim suffered wounds to his leg.

Also in Kirkuk province, two bombings near the home of a police captain in the town of Dibis killed his brother and wounded four others, including the captain himself, police and a doctor said.

In Tal Afar, north of Baghdad, a suicide bomber wearing an explosive belt killed six people and wounded 10 others, officials said.

In Kut, 160 kilometres (100 miles) south of Baghdad, a car bomb exploded on Thursday evening, police Colonel Dhargham al-Assadi said. Six people were killed and 37 others wounded, according to a medic.

Attacks in Al-Garma, Al-Baaj, Badush, Tuz Khurmatu, Mosul, Taji, Khales and Baquba, left seven dead and dozens wounded.

A day earlier, 13 people were killed in attacks north of Baghdad.

On Monday, British security firm AKE Group warned that "terrorists in Iraq may be planning mass casualty explosive attacks against large gatherings of civilians to mark the end of Ramadan later this week".

"We haven't received any specific intelligence on the matter but they (insurgents) may be 'saving up' their willing bombers for the closing period of the month, due around 17-18 August," AKE analyst John Drake said.

Official figures put the number of people killed in attacks in July at 325, the highest monthly death toll since August 2010.