A Buddhist leader and fierce critic of hardliners blamed for attacks on Muslims, is in hospital after reportedly being abducted, stripped naked, and beaten.

Watareka Vijitha Thero, the leader of the Jathika Bala Sena who opposes the actions of Sinhala Buddhist hardliners Bodu Bala Sena (BBS), was abducted and assaulted in the outskirts of capital Colombo on Wednesday night.

Thero was found by a roadside in Panadura town. He was stripped naked, and his arms and legs were tied. His robe and wallet were found nearby. Shehan Kapuge, a local resident, said he had been told the the monk was thrown from a vehicle on Thursday morning.

The monk was taken to the National Hospital in Colombo. Dr Prasad Ariyawansha, the hospital's deputy director, told Al Jazeera: "The monk has suffered numerous cuts in his body and has experienced severe bruising."

Thero has been a strong critic of the BBS and has on several occasions been attacked by the group.

He was most recently verbally abused by the BBS general secretary, Galagoda Aththe Gnanasara, in front of media.

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Thero is a member of the ruling government’s United People's Freedom Alliance and is currently serving as a member of the Mahiyanagana Pradeshiya Sabha, or local council.

BBS has denied any involvement in the assault.

"This is just another step taken by opponents of the BBS to malign us. I can guarantee that our organisation has nothing to do with this attack," said Dilanthe Withanage, an executive committee member of the BBS.

The assault comes few days after hardline Buddhists hurled petrol bombs and looted homes and businesses in several Muslim towns in Sri Lanka, killing three Muslims and seriously wounding more than 80 people.

The attack was believed to have been carried by members of BBS, which has denied responsibility.

Ajith Rohana, a police spokesman, said on Thursday that the police were investigating but have not arrested any suspects.