A missile attack targeted an oil refinery in Iraq's northern city of Erbil on Sunday causing a fire that was later brought under control, the Iraqi security forces said in a statement.

A missile also landed in the outer fence of the refinery without causing any casualties, the statement added.

Earlier on Sunday, the anti-terrorism authorities in Kurdistan region said six missiles landed near the KAR refinery in Erbil, adding they were launched from Nineveh province.

The security forces said they found a launch pad and four missiles in the Nineveh Plain after the attack and defused them.

Iraqi Prime Minister Mustafa al-Kadhimi said the armed forces will pursue the perpetrators of what he called a "cowardly attack", while discussing the security situation in a phone call with Kurdish leader Masoud Barzani, the prime minister's office said on Twitter.

Three missiles also fell near the refinery on April 6, without causing any casualties. Sources in the Kurdistan Regional Government told Reuters then that the refinery is owned by Iraqi Kurdish businessman Baz Karim Barzanji, CEO of major domestic energy company the KAR Group.

In March, Iran attacked Erbil with a dozen ballistic missiles in an unprecedented assault on the capital of the autonomous Iraqi Kurdish region that appeared to target the United States and its allies. Later reports emerged that KAR Group might have been the target for plans to export natural gas to Europe.