Norway's foreign intelligence agency says the rivalry between al-Qaida and Islamic State group extremists has increased and could lead to more terror attacks in the West.

Agency head Lt. Gen. Kjell Grandhagen says the groups are trying "to secure recruits, financial support and ideological leadership" among jihadis in a struggle for supremacy.

Since the 2001 attacks in the United States, al-Qaida has developed a number of affiliates, including IS, which originally was an al-Qaida offshoot in Iraq. Grandhagen said Thursday that Libya has become a haven for jihadi groups in Northern Africa, and noted that groups in several Arab countries recently have pledged allegiance to the Islamic State group.

He said European nations participating in the U.S.-led coalition against Islamic State group faced increased threats, including from jihadis returning home.