Reward up to $28K for suspect in dog's death at Marina del Rey beach (Graphic photo)

Two more animal-welfare groups offered rewards Thursday for information leading to the person who lashed a small dog to a shovel in Marina del Rey, leaving the animal to drown as the tide rose.

The Animal Hope and Wellness Foundation of Sherman Oaks offered a $5,000 reward, while the Santa Barbara-based Davey's Voice offered $3,000. Their contributions push the overall reward being offered in the case to $28,000.

The Los Angeles County Board of Supervisors is offering $10,000, while People for the Ethical Treatment of Animals and the Humane Society of the United States are each offering $5,000.

The dog was found March 16 by a group of lightweight-boat paddlers who said they noticed a blue-handled shovel sticking out of the water. When they got closer, they were shocked to find a mixed-breed puppy tied to it.

A black rope had been wrapped around the dog's neck and the lower portion of the partially submerged shovel in the 14100 block of Palawan Way.

Anyone with information was asked to call sheriff's Deputy Jeff Slutske of the Marina del Rey sheriff's station at (310) 482-6000.

Copyright 2016 FOX 11 Los Angeles: Download our mobile app for breaking news alerts or to watch FOX 11 News | Follow us on Facebook, Twitter and YouTube.