Yet another round of suspicious meatballs has been found in a San Francisco park frequented by dogs. A woman spotted a plate of meatballs with pills sticking out of them Monday morning at the Sunset Reservoir near the corner of Ortega and 24th Avenue.

Police are testing the meatballs to see if the pills are poisonous. A $25,000 reward is being offered by the Animal Defense Fund for information leading to the arrest of the person or persons responsible for these meatballs.

This is the fourth such sighting of suspicious meatballs in San Francisco in the past two years. A dachshund named Oskar died in July 2013 after eating a suspicious meatball in the Twin Peaks neighborhood.

Some residents think off-leash dogs might be targeted because not all owners clean up after them.

To keep your dog safe, keep him on a leash unless he is 100 percent reliable with recall and the command “off!” or “drop it!”

We have frequented the Sunset Reservoir and there are many areas an off-leash dog can get into trouble with poisonous meatballs potentially hiding in the brush on the hills flanking the fences of the reservoir. We stay on the path and only let the dogs run on the grass where we can see them.