(CNN) At least 12 people were killed and 50 others wounded Saturday when missiles pounded an Iranian Kurdish opposition party's base in northern Iraq, party officials said, immediately blaming Iran for the assault.

Three children and three women were among those killed in the attack on the headquarters of the Democratic Party of Iranian Kurdistan, or PDKI, the party said in a statement.

The attack happened in Koysinjaq, a city about 65 kilometers (40 miles) east of Erbil in the semi-autonomous Kurdish region of northern Iraq and some 300 kilometers (186 miles) north of the capital, Baghdad.

The PDKI accused Iran for the attack on its base. "Iran used long-range missiles in a coordinated attack on PDKI's bases and adjacent refugee camps," the statement said.

It also pointed the finger at Iran on Twitter, and posted pictures of smoke rising from the attack.

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