Story highlights A grocer hacked to death a Dalit couple in northern India, police say

A spokesman says the couple owed the shopkeeper 15 rupees (22 cents)

New Delhi (CNN) A man was beheaded and his wife hacked to death after a disagreement with a grocer, according to authorities in India.

The killings took place in the Mainpuri district of the northern Indian state of Uttar Pradesh Thursday, following an argument earlier that day.

The couple, who belonged to the lowest rung of India's caste hierarchy, had owed upper-caste shopkeeper Ashok Mishra 15 rupees (22 U.S. cents) but said they were unable to pay back the money, authorities said.

According to police, eyewitnesses said the couple, who were referred to as Bharat and Mamta, had told Mishra they would pay back their debt at the end of the day, once they had received their wages as laborers.

After a heated argument about 6 a.m. local time, as the couple headed to work in nearby fields, police say Mishra went home, grabbed an ax, and attacked the couple. Both died.

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