An elderly couple were targeted by bogus callers in their home.
Three men went to the property on Back Lane, in Clayton-le-Woods, near Chorley, at around 12.50pm on Tuesday, posing as water board workers.
They told the couple they were working in the area and a pipe had been cut. They claimed there would be an explosion if they did not enter the property and check the water.
When inside the house, the men stole a purse containing £120.
The first man was described as white, in his early 30s, 5ft 9ins tall, of slim build with a black beard. He was wearing a black baseball cap and grey fleece.
The second man was white, in his 30s, 5ft 4ins tall and of stocky build. He had a black beard and wore black woolly hat, black jumper and black gloves.
The third man was white with fair hair.
All three men spoke with foreign accents and were believed to have been travelling in a black car.
Police are appealing for information about the incident or the men and are asking people to call them on 101, quoting log reference 0546 of October 20.
Alternatively, contact Crimestoppers, anonymously, on 0800 555 111 or at Crimestoppers-uk.org.