Cambodian authorities have arrested an opposition senator two days after Prime Minister Hun Sen accused him of treason for comments posted on Facebook.

Saturday's arrest ended a two-day manhunt for Hong Sok Hour, who criticized a 36-year-old border agreement with Vietnam that remains politically sensitive.

The arrest was the latest attack on political opponents. In recent weeks, Hun Sen has used his public speeches to deliver what amounts to arrest orders, which are generally carried out quickly.

Hun Sen has been in power for almost three decades, and while Cambodia is formally democratic, his government is authoritarian and known for intimidating opponents.

Interior Ministry spokesman Gen. Khieu Sopheak said the senator was found on the outskirts of the capital would be taken to court to face charges.