The gang members who abducted the manager of a fish breeding company off Pulau Baik, also known as Pulau Babi near here early Tuesday spoke fluent Malay, claimed a worker at the farm.

The worker who only wanted to be identified as Nus, 22, and had been in the company's employment for four years, said he was sleeping when the incident took place and only knew about it around 5am after being awaken by a colleague.

"I was told by my colleague that the kidnappers spoke in Bahasa Melayu," he said when met by reporters outside the caged fish farm Wednesday.

The incident off Pulau Baik which followed another abduction a month ago at the Singamata resort off Semporna has given rise to suspicion and anxiety among local residents that cross border criminals had long entrenched themselves in Sabah.

The ability of the abductors to speak Malay underscored public perception that insiders are in league with the criminals.

In the 2.45am incident Tuesday, five armed men abducted Yang Zai Lin, 34, a Chinese national from Guangzhao, off Pulau Baik situated about 23km from Lahad Datu town.

Residents believe a foreigner who had just arrived in Sabah would not be readily familiar with the local routes and locations such as the isolated fish farm off Pulau Baik.

Based on this presumption, they want the government to flush out every undocumented foreign presence or foreigners with dubious documents in the Eastern Sabah Security Zone (ESSZone).

Villager Abdul Rahman Mohd Zaid, 66, hoped the government would leave no stone unturned in getting to the root of the menace.

"The security forces must not just go halfway but deal with the situation in full force. In this regard, the government must increase the assets of the security frontliners particularly at the cross border entry points," he stressed.

He also believed that the criminals were foreigners who had settled comfortably in the state.

"The government must carry out large scale operations to check illegal presence in the state and these activities must be ongoing," he added.

Another villager, Fatimah Buhari, 38, opined that close cooperation between local residents and security forces would strenghten security in the ESSZone.

"The government should not readily issue personal documents or identity cards to individuals without subjecting them to stringent scrutiny even if they had been staying in the country for a very long time," she added.

Last April 2, two women including a Chinese tourist were abducted by seven armed men at the Singamata reosrt off Semporna.

The Chinese, who is also a student from Shanghai was identified as Gao Hua Yuan, 29, while the other victim, a Filipina aged 40, was identified as Marcy Dayawan or Mimi.

In November last year, a tourist from Taiwan was shot dead and his wife abducted by a gang off Pulau Pom Pom in Semporna.