CAIRO (AP) — Human Rights Watch says that activists in western Libya have been physically attacked and threatened by armed groups, some affiliated with U.N.-backed government based in the country's capital, Tripoli.

The statement by the New York-based watchdog on Thursday says that Libyan "authorities seem unable to rein in the attackers, enabling them to operate with impunity."

It says many activists have fled the country after threats or attacks by armed groups and militias.

HRW also urged the Tripoli-based government to hold armed groups, especially those aligned with it, accountable if they threaten, harass, or assault activists.

Libya descended into chaos following the 2011 civil war that toppled and killed dictator Moammar Gadhafi.

The oil-rich nation is now split between rival governments and an array of militias with different alliances.