A brutal mob killing of a Sri Lankan man accused of blasphemy in Pakistan has sparked protests in both countries, with Pakistan"s leader condemning the vigilante violence, BBC reported. Priyantha Diyawadanage, 48, a factory manager in the city of Sialkot, was beaten to death on Friday and his body set alight. More than 100 people have been arrested so far, said Pakistan PM Imran Khan. He has described the incident as a "day of shame" for his country. The victim"s family in Sri Lanka have told the BBC they are in despair. His wife, Nilushi Dissanayaka, called on both Pakistan and Sri Lanka"s governments to conduct a full investigation to "bring justice to my husband and my two children". "I saw that he was being attacked on the internet... it was so inhumane," she said. Videos of the lynching proliferated across social media over the weekend, and showed scenes of the incensed crowd dragging Diyawadanage from his workplace and beating him to death. They then burned his body, and several people in the crowd were seen taking selfies with his corpse. The violence had begun after rumors spread that Diyawadanage had allegedly committed a blasphemous action, in tearing down posters with the name of the Prophet Muhammad, local police chiefs said. But a colleague, who rushed to the site in a bid to save him, told the Associated Press of Pakistan that Diyawadanage had only removed the posters as the building was about to be cleaned. His wife has also refuted the blasphemy claim. "I totally reject reports that said my husband tore down posters in the factory. He was an innocent man," she told the BBC. "He was very much aware of the living conditions in Pakistan. It is a Muslim country. He knew what he should not do there and that"s how he managed to work there for eleven years." The scale of the vicious killing on Friday — involving hundreds of people - has shocked the nation and sparked vigils. Prime Minister Imran Khan condemned the "horrific vigilante attack" and vowed that "all those responsible will be punished with the full severity of the law". Blasphemy is defined as speaking insultingly about a particular religion or god. In Pakistan, it can carry a potential death sentence for anyone who insults Islam. The country"s blasphemy law prohibits disturbing a religious assembly, trespassing on burial grounds, insulting religious beliefs or intentionally destroying or defiling a place or an object of worship. Making derogatory remarks against Islamic personages is an offense - and in 1982, a clause prescribing life imprisonment for "wilful" desecration of the Holy Qur"an was added. In 1986, a separate clause was inserted to punish blasphemy against the Prophet Muhammad (peace be upon him) and the penalty recommended was "death, or imprisonment for life". In Pakistan, even unfounded accusations can incite protests and mob violence against alleged perpetrators. Human rights critics have long argued that minorities are often the target of accusations. He said he had also spoken with Sri Lankan president Gotabaya Rajapaksa "to convey our nation"s anger and shame to the people of Sri Lanka." Sri Lankan authorities have yet to comment fully on the case, fearing potential unrest and retribution against Muslim communities locally. Diyawadanage"s body is due to be returned to Sri Lanka on Monday, and some expect protests to be held in the capital Colombo.