Melbourne has been rocked by two random stabbings, with an elderly man and a young childcare worker both allegedly knifed in the back in broad daylight.

The 25-year-old woman was allegedly attacked by a 16-year-old boy at M-City Shopping Centre on Blackburn Road, in Clayton, at about 7.50am on Thursday.

A passer-by assisted the Mount Waverley woman, who suffered serious upper body injuries after she was followed onto an escalator and allegedly stabbed.

She was rushed to The Alfred in a serious but stable condition.

The 16-year-old boy fled the scene before he was taken into custody at a nearby medical centre.

It’s understood the two did not know each other.

The teenager has since been charged with intentionally causing injury, recklessly causing injury, assault with a weapon, possession of a controlled weapon, theft and committing an indictable offence while on bail.

He was remanded in custody to face a children’s court at a later date.

A passer-by assisted the young childcare worker, who suffered serious upper body injuries after she was followed onto an escalator and allegedly stabbed (pictured)

The elderly man was captured on CCTV holding his hands to his lower back as he slowly made his way to a nearby cafe to seek help (pictured)

Just over 24 hours later, a 71-year-old man was forced to seek refuge in a cafe after he was allegedly stabbed three times in the back during his morning walk.

The man walking near Crighton Reserve in Port Melbourne about 5.20am on Friday when he was approached by a stranger and attacked.

The elderly man was captured on CCTV holding his hands to his lower back as he slowly made his way to a nearby cafe to seek help.

‘He wasn’t too bad, you know, he could still talk… I was pleased about that. But he was bleeding, he lost a lot of blood,’ witness Mohammad Hassoun told 9News. ‘They done it for nothing, they didn’t even try to take nothing from him, just stab and go.’

The man was rushed to hospital with serious injuries.

Police have appealed to the public for help identifying the offender responsible for the ‘shocking’ attack which occurred during peak dog-walking time.

The man is described as Caucasian, aged between 30 and 40 years old, around 182cm tall, possibly with brown hair, and dressed in all black.