The couple’s eight-year-old son Krishna, who was travelling with them, survived the accident, officials said. (Representational)

A migrant worker and his wife were killed on Saturday morning when the auto they were travelling in to get to Darbhanga district was hit by a mini-truck on the Lucknow-Agra Expressway in Bangarmau region of Unnao district.

The couple’s eight-year-old son Krishna, who was travelling with them, survived the accident, officials said.

The deceased were identified as Ashok Chowdhary (35) – who used to drive an auto in Delhi – and his wife Chhoti (33). The family had left the national capital for Darbhanga on Friday.

According to the police, the auto had pulled over to the side of the highway and Krishna had stepped out to relieve himself when a truck rammed the vehicle from behind.

Both Ashok and Chhoti suffered serious injuries, they added. Local residents rushed the couple to a hospital where they were declared ‘brought dead’.

The bodies were sent for a post-mortem, Bangarmau Police Station Circle Officer Gaurav Kumar Tripathi told The Indian Express. Krishna suffered no injury and is currently with officials of the district’s Child Line, a police officer said.

The police have seized the truck but the driver managed to escape, said Bangarmau Police Station House Officer Shyam Pal Singh.

Uttar Pradesh Chief Minister Yogi Aditynath announced an ex-gratia of Rs 2 lakh to the next of kin and directed officials to make arrangements to send the bodies to Bihar.