A robber threatened a post office worker with a scalpel and made away with a four-figure sum of cash.

The man burst into the branch at Eastwood Boulevard, in Westcliff, at around 5.20pm yesterday and threatened the worker with the surgical instrument, demanding the female worker open the till.

He stole a four-figure sum.

The man, who is aged in his late 30s, is still  at large as police carried out a search of the area but did not find him.

He was described as white, aged in his late 30s, with dark hair and a local accent. He wore a navy blue hooded top, blue jeans and trainers.

Witnesses or anyone with information are asked to contact Rayleigh CID on 101.

Alternatively, they can contact Crimestoppers anonymously on 0800 555111 or www.crimestoppers-uk.org.