It was alleged that Thewarapperuma attempted to assault party leader Ranil Wickremesinghe at the Parliamentary group meeting a few days ago.
A UNP Parliamentarian told 'Asian Mirror' that Thewarapperuma was drunk when he attended the Parliamentary group meeting.
UNP sources told 'Asian Mirror' that MP Ranjan Ramanayake, who prevented Thewarapperuma from attacking the party leader, had complained over the latter's behaviour to the party hierarchy.