Thieves stole jewellery worth more than £12,000 during a burglary at a home in Claudius Way, Witham.
Police said a kitchen knife was used to open a bedroom safe while the family of four were out at around 11.45pm on Sunday, July 20.
The burglar alarm was ripped from the wall during the incident.
A number of Indian-style chains, bangles and necklaces worth £8,000 and rings worth £2,000 were stolen.
A matching diamond necklace and earring set worth £1,500 and eight pairs of earrings with a combined value of £1,250 were also taken.
The thieves also took several credit cards and the keys to a Mazda and BMW but the cars were not stolen.