By Trinna Leong
GEORGE TOWN, Malaysia (Reuters) - Police in Malaysia have arrested 20 people in a widening investigation into the murder of at least 18 Myanmar nationals in the state of Penang since January.
Twelve Myanmar migrants have confessed to their role in nine of the murders, which have seen bodies dumped - many with their throats slashed - across the state, Penang police chief Abdul Rahim Hanafi told reporters on Thursday.
Police believe two unrelated groups are behind the murders, Abdul Rahim said. All of those arrested are from one group.
The widening net follows the discovery of a "slaughterhouse" last week, where police say at least two victims were believed to have been killed and dismembered.
Media and community groups have speculated that the murders have been perpetrated by Muslims from Myanmar, likely including stateless Rohingya, as payback for religious violence in Myanmar since 2012.
Myanmar community organisations have told Reuters the majority of the victims were Buddhists. Police have not revealed the ethnicity of the victims and have denied any ethnic or religious conflict.
"This is a feud between Myanmar people. It is not a religious conflict. These are only vengeful murders that were brought over here from Myanmar," Abdul Rahim said, without elaborating.
Police have found an additional 10 unidentified bodies of people who appear to have been killed in a similar manner, he said.
Police released the pictures of two men from Myanmar, identified as Mohammad Yahyar Khan and Lokman, who are wanted for questioning.
Buddhist community leaders have accused the police of being slow to act and refusing to acknowledge a religious or ethnic motive.
"It's just talk when the police say 'no Rohingya are involved'," Aye Tun Maung, a leader of Buddhist community group the Arakan Refugee Relief Committee, told Reuters.
"It's Rohingya killing the Rakhine. Some of the dead are also Bamar and Shan," he said, referring to other ethnic groups of Myanmar's majority Buddhist population.
Outside the house where some of the murders allegedly took place, neighbours described the two suspects arrested there, both men, as observant Muslims who appeared to be South Asian.
"They're Muslims. Sometimes I would give them a ride when I went to the mosque," said Fizal Abdullah, 40.
More than 60,000 migrants from Myanmar live in Penang, many of them asylum seekers and refugees employed in factories and on construction sites.
Penang is also a destination for stateless Rohingya, more than 100,000 of whom have fled Myanmar since religious violence in 2012.
(Writing by Aubrey Belford in Bangkok; Editing by Simon Webb and Robert Birsel)