RALEIGH, N.C. — On a hot summer day, there is nothing more refreshing than a dip in a pool. But on Sunday, some Cary residents had to swim elsewhere because vandals contaminated the water for the second time in a month.

"Contamination, let's say, defecation on the diving board, our slide," said James Leifeste, director of the Lochmere Swim Club. "As we're cleaning throughout the day, we found things in unusual spots, hidden under tables."

Cary police are investigating the incidents.

"It's very possible that it could have been teenagers, young individuals that may have done this," said Capt. Kenny Williams, of the Cary Police Department. "We don't have any suspects at this time, but we hope anyone with knowledge of this will call us."

At least two other local pools have dealt with the same kind of vandalism this summer. Even though kids may be responsible, it is no childish prank. Under state health laws, fecal contamination can close a pool anywhere from 24 to 36 hours. During that time, high levels of chlorine are used to clean the water.

"Folks join to come and have a good time here and when someone then takes away that enjoyment, they know exactly what they're doing, who they're doing it to, so it's something that's extremely deliberate and disturbed," Leifeste said.

Apex police confirmed another pool was vandalized in a similar manner Thursday. Investigators do have some leads in that case. Right now, Cary and Apex police do not believe the cases are related. Authorities believe the vandals knew what they were doing and intended to shut down the pools.