The PSNI has asked the people of the Crossmaglen area, not to approach any suspicious looking objects and instead report them to the police.
A police spokesman said nothing untoward had yet been found and appealed for anyone with information, or who may have seen something suspicious, to contact them.
Danny Kennedy, Ulster Unionist MLA for Newry and Armagh, said: "The fact that the PSNI have had to issue a warning to the public to remain observant for suspicious looking objects in the South Armagh area is a matter of great concern.
"The vast majority of the people in South Armagh want to live in peace, free from the threat of terrorism.
"Those who are trying to kill innocent people with a bomb attack in Belfast and heighten tensions with bomb alerts in other areas offer nothing, but a corrupt ideology.
"They might copy the tactics of the Provisional IRA, but like them, they will still not achieve a United Ireland," he added.
"Politics is the only way forward."