AIKEN --- Yvonne Key says the convenience store where she works has been hit by armed robbers three times this year.

After the third one occurred a couple of months ago, the Manis Mart in Beech Island took extra precautions, she said.

"We put up bullet-proof glass over our counter," she said.

Armed robbery cases are up in Aiken County this year, with 58 through July 30. There were 48 during the same time span last year, said Aiken County sheriff's Capt. Troy Elwell.

He said several bank and convenience store robberies that occurred a couple of months ago have caused the increase, though his department doesn't track armed robbery cases involving businesses.

Capt. Elwell has repeatedly said he doesn't believe the economy has caused the uptick, and he noted no banks have been robbed since July 1 in the county.

Police say they're still looking for the Manis Mart suspects and are continuing concentrated patrols. Police suspect juveniles, some as young as 15, to be involved in a couple of the robberies.

The Richmond County Sheriff's Office also has seen an increase in armed robberies, though it also doesn't track cases involving businesses.

Through June, the most recent month with statistics available, Richmond County had 195 armed robberies, an increase from 168 in the same time span a year ago, according to the sheriff's office's Web site.

This year, Columbia County has had 16 armed robberies. From January to July last year, the county had seven.

Reach Preston Sparks at (803) 648-1395, ext. 110 or preston.sparks@augustachronicle.com