The accused beat up the couple with a baton while they were sleeping in their shanty. (Representational)

A 23-year-old woman died and her husband was injured in southeast Delhi's Hazrat Nizamuddin area after they were allegedly beaten up by a relative who suspected that he had lost his job because of the couple, the police said on Thursday.

However, the accused, Rati Ram, told the police that he attacked Sita and her husband Mangal, 25, as he was angry after he got an electric shock from a wire dangling from the gate of their house.

The accused is Mr Mangal's cousin.

The incident took place on Wednesday night and we received information around 1:30 am, the police said. All three worked as labourers with Tara Chand contractor at the Public Works Department (PWD), they said.

According to Mr Mangal's statement to police, Rati Ram was sacked by his boss two days ago as he was a troublemaker, who often fought with his colleagues and was addicted to alcohol. The accused suspected that he was sacked because Mr Mangal and Ms Sita had complained to their boss about him, a senior police officer said.

The accused then beat up the couple with a baton while they were sleeping in their shanty along with their six-month-old daughter, the police said, adding that he first attacked Mangal and when Ms Sita came in between, he thrashed her.

Ms Sita suffered injuries on her head while Mr Mangal, who also sustained injuries, managed to survive, the officer said. The couple was rushed to the AIIMS, where Ms Sita was declared brought dead, and her husband is undergoing treatment, the police said.

A trap was laid and the accused was nabbed from Sarai Kale Khan, a senior police officer said. The police said the accused, who was drunk at the time of the incident, has been detained. A case under relevant sections of the IPC had been registered against him, they added.

During interrogation, the accused disclosed that he consumed liquor on Wednesday evening and when he came near Mr Mangal's shanty, he got an electric shock from a loose wire, the officer said. He held Mr Mangal responsible for the electric shock.