Anti-government protesters in Eilat say a vehicle drove past their rally and sprayed them with tear gas before fleeing the scene.
Police at the rally were also hit by the gas, the Walla news site reports.
The police say they are investigating the incident.
“This incident is a direct result of the incident by the defendant Netanyahu,” protest organizers say in a statement.
Channel 12 says a pro-Netanyahu activist attacked a protester outside the Prime Minister’s Residence on Friday, and another posted, then deleted, a clip on Facebook saying protest opponents should bring weapons to the rallies.
Thousands are expected to attend rallies throughout the country on Saturday. Previous protests devolved into violence between anti-government demonstrators and counter-protesters, but in recent days the protests have largely been calm.