A search continues for two young children after heavy rains caused dangerous flooding in Bucks County on Saturday. On Monday, authorities identified five people who drowned in the flood.

“These people weren’t driving through high water. They were caught,” said Upper Makefield Township Fire Chief Tim Brewer. “It was a flash flood phenomenon. … The wall of water came to them.

Police on Monday identified the missing children as 2-year-old Matilda “Matty” Shiels and 9-month-old Conrad Shiels. Authorities confirmed the children’s mother, 32-year-old Katie Seeley, was among the dead. The rest were identified as Susan Barnhart, 53, Yuko Love, 64, Linda Depiero, 74, and Enzo Depiero, 78.

Bucks County Coroner Meredith Buck said drowning was the cause of death for all five fatalities.

Brewer said the search for the missing children will continue through Tuesday with additional help from around Pennsylvania and New Jersey. He said some search operations would continue through the night.

Weather conditions Monday allowed first responders to use more resources in the search, including K9 units, drones and underwater search equipment, Brewer said. Search teams from Bucks, Chester and Delaware counties, as well as New Jersey, are assisting, Brewer said.

“We’ve basically tripled the number of properties, mostly due to weather conditions,” he said early Monday. “This will be a major undertaking involving the coordination and cooperation of many departments and agencies across the state and region.”