A political ally says Sri Lanka's former army chief and presidential candidate has been arrested on sedition charges.
Opposition politician Rauff Hakeem says former army chief and defeated presidential candidate Sarath Fonseka has been detained.
Fonseka and President Mahinda Rajapaksa were once strong allies who combined to defeat the Tamil Tiger rebels, ending the country's 25-year civil war last May. But they later fell out, and Fonseka quit his post.
They contested a bitter election last month for the presidency, won by the incumbent, Rajapaksa.
Since the Jan. 26 election, security forces have attempted to round up Fonseka's followers and also raided his office.
Fonseka has vowed to contest parliamentary elections due by April.