Two people were injured when a man burst into a Mid Sussex post office brandishing a knife and demanding money.

The would-be robber fled empty-handed from the sub-post office in Jengers Mead, Billingshurst, but not before he had slashed a man's arm with the knife and pushed a woman out of his way.

The two injured customers were taken to St Richard's Hospital in Chichester. Neither has life-threatening injuries.

Police are appealing for information about the incident, which took place at 10.30am yesterday.

The offender is described as between 18 and 23, 6ft or 6ft 1in tall, with a shaven head and olive skin, similar to a Mediterranean appearance. He was clean shaven.

An off-duty police officer was injured when he tackled a building society robber.

The man had stolen an undisclosed amount of money from the Portland Building Society in Hassocks at 11.40am yesterday.

The officer was driving through the village when he stopped and challenged the offender.

He attempted to detain the man, who threatened him, and a violent struggle ensued. The officer needed hospital treatment for a dislocated finger.

Members of the public assisted and uniformed officers quickly arrived.

A man was arrested and was last night in custody at Crawley police station.

Anyone with information should contact the police on 0845 6070999.