Iraq parliamentary candidate killed in his home near Mosul
Farouq Mohammad Zarzour was stabbed to death after men broke into his house in the village of al-Lazzaga, Captain Ahmed al-Jubouri from the nearby Qayyara police told news agency Xinhua.
Another report from Kurdistan 24 said the university professor was shot.
The Islamic State group has claimed responsibility for the murder. In a statement on the messaging app Telegram, IS said Zarzour was killed because he was "an atheist".
Zarzour was competing in the polls within the Wataniya Coalition, led by former prime minister Ayad Allawi.
Ryadh al-Jubouri, a relative of the victim, told Xinhua that a group of men visited the house of the candidate, a teacher at Tikrit University in Salahudin province, posing as supporters for his campaign.
In a video posted on Facebook the day before he died, the 45-year-old called on voters to be wary of outgoing candidates "and those who buy votes," in a message featuring him carrying his six-year-old son Rayan in his arms.
In the video, he promised "a strong government - one that will take care of poor, families of martyrs, reconstruction and citizens".An investigation into the attack is under way.
The UN last month condemned attacks targeting parliamentary candidates after a Kirkuk hopeful was targeted in a car bombing.
One person was killed and 11 others injured when the car exploded after the convoy of a Turkmen Front candidate passed through a checkpoint.The car of a candidate from the Wataniya Coalition was also reportedly fired at, south of Baghdad.
Parliamentary elections will be held on May 12, with around 7,000 candidates competing for the 329 seats in the Iraqi parliament, the first general election since Prime Minister Haider al-Abadi declared victory over the Islamic State group (IS) in December last year.
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However the country still experiences frequent attacks as the extremist group attempts a resurgence after losing a vast majority of its so-called "caliphate" spanning across Iraq and Syria.
Many are expecting an escalation of terror attacks as election day approaches and IS aims to deter Iraqis from going to polling stations.