Major police operation as bomb squad is called to a busy Sydney road.

There were dramatic scenes in Sydney’s west this morning after a major police operation shut down a busy road for four hours.

The police bomb squad was called to Windsor Rd, Northmead, at around 4.40am after a man lay down in the middle of the road and refused to move.

Footage from 7 News showed the man in a high-vis shirt resting on a bag while scratching a dog that was sitting beside him.

The police operation shut down part of Windsor Rd in both directions with Pennant Hills Rd also closed westbound and the Eastbound Cumberland Highway closed at Kleins Rd.

People were warned to avoid the area.

The operation ended about four hours later when the man was arrested.

Footage showed armed officers approaching the now-shirtless man as he laid face down on the ground.

The man has since been taken to Castle Hill police station.