Malaysian police say they have arrested more than 50 people in the state of Sabah for suspected links to a deadly invasion by Filipino fighters.
Authorities said they made the arrests on Friday amid clashes between security forces and members of the Sulu Royal Army, a group from the southern Philippines that claims Sabah as their own.
About 60 people, including 52 fighters and eight Malaysian police officers, have been killed in fighting that erupted a week ago.
Malaysia has rejected a call by the fighters' leader for a ceasefire in a farming region where the fighters are being pursued.
Scores of followers of a self-proclaimed Philippine sultan landed in the state on Borneo island last month to assert a long-dormant territorial claim in what has become Malaysia's worst security crisis in years.
The main group of fighters were holed up in a farming village for three weeks until two deadly shootouts with security forces last weekend triggered a military assault that scattered them amid vast oil palm plantations.
There have been reports of other gunmen elsewhere along Sabah's coast that have raised fears of a wider infiltration by fighters and the possibility they may have been aided by sympathisers already in Malaysia.
"I am afraid when I am working, worrying something will happen when I am on the road," said truck driver Mohammad Macor, a resident of Felda Sahabat 22, a village 2km from the cordoned-off conflict zone.
In the Philippines, the government of President Benigno Aquino has said it has formally asked Malaysia to ensure humanitarian treatment for 10 Filipinos who it says have been captured. Malaysia has not confirmed that account.
The incursion was carried out by a group of followers of Jamalul Kiram III, the self-proclaimed heir to the former southern Philippine sultanate of Sulu, which had a historical claim to Sabah.
Kiram's people say about 235 people took part in the incursion. They also said that 10 had been captured.
Source: Al Jazeera