One week after officials warned against swimming in Grand Lake, concerns are raised over blue-green algae at another Oklahoma lake.

US Army Corps of Engineers spokesman Ross Atkins says tests are underway to determine whether it's safe to play in Fort Gibson Lake:  “We see blooms now at the Chouteau Bend portion of Fort Gibson Lake, and we may be seeing more at other lakes.”

Atkins says most algae is harmless, “But occasionally we get a bloom that has some toxicity to it, and that’s the kind we get concerned about.”

Atkins says they should know the results of samples taken this week sometime Friday.

If you want to report presence of blue-green algae, contact the Grand River Dam Authority at 918-824-1074 or the Department of Environmental Quality at 1-800-522-0206.