A son took his mother's dead body on a 36-mile bus journey home after she died while they were on a day out.
The 88-year-old woman is believed to have died in her wheelchair on a bus home from Lancaster to Preston, a 25-mile journey.
Police said they believe the 52-year-old son, who is thought to have learning difficulties, was overcome by grief after he discovered his mother had passed away.
"She died when they were on a day out," said a spokesman for Lancashire Police.
"He did not know what to do. He wanted to just get his mother home. It is just very tragic."
Police said the son, who has not been named, got off at Preston bus station and boarded another bus bound for Chorley, a further 11 miles away, with his mother's body still in the wheelchair.
It was here that suspicions were raised, when a security guard asked the son if his mother needed an ambulance. The son attempted to flee and the guard gave chase before contacting police.
Officers stopped the son in a nearby street and an ambulance was called. The pensioner was pronounced dead at the scene.
Police said they are not treating the woman's death as suspicious.