Seven motorists were arrested at a police checkpoint Friday night in Petaluma, and 14 were apprehended during a similar operation in Rohnert Park, public safety agencies reported.

Petaluma officers operated a checkpoint on Payran Street near Jefferson Street from 6 to 9 p.m., then moved to a site on East Washington Street at Lakeville Street from 10p.m. until 2 a.m. Saturday, Petaluma Sgt. Ken Savano said.

A total of 551 vehicles went through the checkpoints and 532 drivers were screened for driving under the influence and for license violations. Five drivers were arrested on apparent license violations and two on suspicion of DUI, Savano said. One vehicle was towed from a checkpoint.

Rohnert Park police maintained a checkpoint for eastbound drivers of Rohnert Park Expressway near State Farm Drive from 7 p.m. to 3 a.m., Sgt. Aaron Johnson said.

A total of 1,233 vehicles passed through the checkpoint and 1,212 drivers were screened. Fourteen drivers were cited for driving without a license, he said.

Steven Higdon of Santa Rosa was stopped for a vehicle code violation near the Rohnert Park checkpoint at 1:24 a.m. and was arrested on suspicion of driving under the influence of drugs, Johnson said.