Gunmen have shot dead a senior oil official working for Iraq's state-run North Oil Company (NOC), police and company officials have said.

Saad al-Karbalaie, NOC's director of operations, was killed in Kirkuk on Sunday after armed men forced him to stop his vehicle as he was leaving his office, going on to shoot him, police sources said.

There was no immediate claim of responsibility for the attack on Karbalaie, who was supervising production and export facilities in the northern oil city.

The incident follows several attacks in Baghdad on Sunday in which at least seven people were killed in a series of blasts in public places. Al Jazeera's Jane Arraf, reporting from Baghdad, said at least 19 were injured in the blasts.

Months of violence

Iraq, a major oil producer and OPEC member, faces security challenges from both the Islamic State of Iraq and Levant (ISIL), which controls a third of the country, and a sectarian conflict exacerbated by the group's presence.

The Baiji refinery, north of Baghdad, is a focal point for government efforts to slow the advance of ISIL.

The complex has changed hands several times in months of fighting.

Meanwhile, the US and its allies staged 17 air strikes against ISIL positions in Syria and 10 strikes against the group in Iraq on Saturday, the US military said.

In Syria, nine of the air strikes hit ISIL positions near Kobani, five struck near Aleppo and three hit near Tal Abyad, the US military said in a statement on Sunday.

Source: Agencies