COLOMBO, Sri Lanka (AP) — An opposition leader says Sri Lankan police have prevented about 1,000 ethnic minority Tamils from traveling to a protest march to demand justice for relatives who have disappeared or been detained since the end of the country’s civil war in 2009.

Mano Ganeshan, who leads the opposition Democratic People’s Front, says buses packed with about 1,000 Tamils were prevented from leaving the northern town of Vavuniya to make the 210-kilometer (130-mile) journey to the capital, Colombo, for Wednesday’s protest. The protest was subsequently canceled.

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He says government forces and police intimidated and warned the bus drivers not to proceed with the journey.

Military spokesman Brig. Ruwan Wanigasooriya rejected the allegations and said police stopped the buses to prevent possible clashes in Vavuniya.