A 94-year-old grandmother is seriously ill in hospital with a fractured skull and partially severed finger after being beaten in her own bed as she slept.
Police said Emma Winnall also suffered a broken arm and wrist in the "vicious" and "sickening" assault at her West Midlands home.
Her carer raised the alarm at 9am on Tuesday but detectives said the attack, which left her with potentially life-threatening injuries, could have occurred at any time from 9pm on Monday night.
Mrs Winnall, of Pensby Close, Moseley, in Birmingham, was taken to hospital and remains under sedation after emergency surgery, which involved inserting metal plates into her arm.
Detectives have been unable to determine a motive for the attack. Nothing was stolen from the property and the interior was largely undisturbed.
A photograph of Mrs Winnall in hospital has been released at the request of her daughter as part of a police appeal for information.