Police in Pakistan say investigations into the multiple killings have commenced. Photo: AFP

At least nine members of a family have been killed in an armed attack in northwestern Pakistan.

The assailants barged into their home around midnight and killed three women and six men in the city of Batkhela in Malakand district of Khyber Pakhtunkhwa province

"We have arrested the suspected killer, who was the son-in-law of the slain family," Rab Nawaz, a local administration official, said.

"The wife of the suspect was having some dispute with him and she returned to her father’s home and was staying there," he said.

He added that on Wednesday night, the son-in-law came along with two other people, entered his father-in-law’s home and killed all nine people, including his wife, while they were sleeping. Only three children survived the attack.

Pakistan is celebrating the Muslim Eid al-Adha holiday, but people in the area were in mourning.

"It was a tragic incident, and the whole city is in shock over this brutal killing of the family," said Abdul Hakim, a local resident.

Hakim said local people also staged a protest demanding tough punishment for the culprits.

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