14yo boy charged over two Sydney assaults

A teenage boy has been charged over two "frightening" attacks on young women in Sydney's west.

The alleged assaults happened barely 500 metres apart in Bonnyrigg on Tuesday night and Thursday lunchtime.

In the first attack, a 23-year-old woman was grabbed from behind while walking and thrown to the ground.

The attacker allegedly covered her mouth with his hands, but ran off after she struggled and screamed.

Two days later, another 23-year-old walking along the T-way was grabbed from behind, placed in a choke-hold and dragged behind a bus stop before being punched in the head.

Detective Superintendent Peter Lennon on Friday described the assaults as "frightening".

"I just can't understand how this could happen pretty much in the middle of the day in a very public area," he told reporters.

Police on Friday arrested a 14-year-old at a property in Bonnyrigg, later charging him with two counts of assault occasioning actual bodily harm.

He was refused bail to appear at Parramatta Children's Court on Saturday.