Iran TV: 5 people stabbed to death in family home in north Iran's state TV is reporting that 5 people were stabbed to death in a house in the northern Gilan province, including 4 members of the same family

TEHRAN, Iran -- Iran's state TV is reporting that five people were stabbed to death in a house in the northern Gilan province, including four members of the same family.

Monday's report quoted deputy prosecutor Aliasghar Heidarnejad as saying the victims were a father, mother, grandfather and daughter, as well as the daughter's friend.

Heidarnejad says a suspect was arrested, but police were continuing their investigation into other potential killers. There was no immediate word on motive.

In was the deadliest domestic killing incident in Iran since March, when a man shot seven members of his wife's family dead in the southwestern city of Dezful.

In January 2017, a man gunned down five people in the central Iran. A month earlier, a man killed 10 relatives in a remote southern rural area.