A hunt has been launched for a knifeman who held up terrified staff at a pet store as he demanded cash.

The masked robber struck at 6.20am on Wednesday as employees at Pets At Home, on the Capitol Centre retail park at Walton-le-Dale, near Preston, prepared to open the store.

He rang the buzzer at the back of the store, and staff, believing it to be some of their other colleagues arriving for their shift, opened the door.

He burst in armed with a 12 inch tapered kitchen knife and threw a bag at a 24-year-old worker and his colleague, an 18-year-old woman.

Police said he shouted at them to “fill it with money.”

The frightened employees gave him an undisclosed amount, thought to be thousands of pounds, from the safe.

The thug then fled through the back of the premises, which leads into a yard behind the shops.

It is not clear how he got away.

The store declined to comment, but today Det Insp Jane Webb, investigating the incident for Preston Police, said: “This must have been a terrifying experience for the staff members involved although thankfully no-one was hurt.

“I would appeal for anyone who may have seen anything suspicious to get in touch with us.”

She added: “It may be that people were on their way to work or out walking the dog and saw something that could help us catch this man.”

The robber is described as white, of average height and build.

He was wearing dark clothing, and had a balaclava covering his face. It appeared to have holes which had been roughly cut out for his eyes and mouth.

The victims told officers he was carrying a bag, which was black with a grey trim, and was similar in style to a laptop or courier bag.

Anyone who saw anything suspicious, or who has any information should call Preston Police on 101 or Crimestoppers on 0800 555111.