The operation used needles with strong sedatives to catch the dogs in Mueng district at 10am. It succeeded in capturing only two dogs on Friday.
Officials said they might take up to seven days to round up all the stray dogs in the downtown area due to the large number of connected alleys that make escape easy.
Local residents complained that the stray dogs in the area are aggressive and often chased motorcyclists, leading to at least two fatal accidents.
The accident that led to the round-up efforts happened at 3am Tuesday when a pack of dogs mauled and damaged the car of Somnuek Semkham, 35 who parked it in front of her boarding house.
The officials said the captured dogs would be monitored in cages for seven days, after which they would be released into a shelter for stray dogs in Muenag Ratchaburi municipality.