A 25-year-old man from Sundarapuram in Coimbatore murdered his grandmother on Monday, allegedly after she refused to give him a share of the compensation that she had received for the death of her son in a road traffic accident.

R. Manonmani, 80, a resident of Sathiyamoorthi Nagar at Sundarapuram in the city, was murdered by his grandson M. Sivakumar.

The police said Sivakumar’s father Murugesan died in a road traffic accident at Velanthavalam near K.G. Chavadi three years ago. A total of ₹15 lakh was awarded to the family as compensation in the case related to the accident.

While Murugesan’s wife M. Lakhsmi received ₹6 lakh, his two brothers and Manonmani received ₹1.5 lakh each. The counsel who represented the case for the family in the motor accidents claims tribunal was paid ₹4 lakh as his fee, said the police.

Sivakumar, according to the police, had been demanding Manonmani to give him a share of the amount she had received from November last year. However, the woman refused to give him money.

He approached his grandmother around 1.30 p.m. on Monday and reiterated his demand for a share. As the woman refused, he slit her throat with a knife and escaped. The woman was rushed to the Coimbatore Medical College Hospital, where she died.

The police were on the lookout for Sivakumar.