Panchayat president Anumol Jose said the incident occurred on October 22.
The male stray aged around 1.5-2 years was completely vaccinated recently with administration of three times immunisation and two doses of anti-rabies vaccines.
“The only way to improve the situation is to regulate the business. We will microchip all the 150-odd horses in Chennai, predominantly used for joyrides on Marina.
The two were arrested and released on station bail on Monday night.