Shia militias in Iraq have kidnapped and killed scores of Sunni civilians in recent months, a report by campaign group Amnesty International has said.

The killings were in apparent revenge for attacks by Islamic State (IS).

Amnesty said the militias had been supported and armed by the Iraqi government and operated with impunity.

Prime Minister Haider al-Abadi, who took office last month, has admitted to previous "excesses" by security forces and vowed to govern for all Iraqis.

He has not yet commented directly on allegations contained in the Amnesty report but has previously said Iraq faces an "existential" battle against militants from IS, also known as Isis or Isil.

Mr Abadi has also acknowledged, in what is believed to be a reference to Sunnis, that his government must address the "legitimate grievances" of the Iraqi people.

The Amnesty report, based on interviews conducted in Iraq in August and September, provides details of what it says were sectarian attacks carried out by militiamen in the cities of Baghdad, Samarra and Kirkuk.

It says scores of unidentified bodies have been found, many still handcuffed and with gunshot wounds to the head, suggesting execution-style killings. Many others who disappeared remain unaccounted for.

Amnesty says that in Samarra, a mainly Sunni city north of Baghdad, it obtained details of more than 170 Sunni men abducted since June.

More than 30 were taken from or near their homes in a single day - 6 June - before being shot dead. Their bodies were dumped nearby.

"The killing spree seems to have been in reprisal for a brief incursion into the city the previous day" by IS fighters, Amnesty says.

(BBC)