The western and northern suburbs of Philadelphia were hit by widespread flooding and numerous reports of water rescues as heavy rains swept through the region Thursday evening.

Late Thursday night, televised reports said a pregnant woman and her 8-year-old son were found dead in a vehicle that had been swept away by flood waters in Berks County.

Just before 5 p.m., the National Weather Service in Mount Holly, N.J., issued a rare “flash flood emergency” for northwestern Montgomery County and southeastern Berks County.

“This is an extremely dangerous and life threatening situation! Do not attempt to travel in those areas! Serious flash flooding is ongoing with a number of water rescues reported!” the NWS posted on Twitter.

Shortly before 7 p.m., the Montgomery County Department of Public Safety reported that the “rains have eased up, but the challenges of high water remain in this area.”

Flash flood warnings were in effect for the Philadelphia area and South Jersey through 10:15 p.m., the NWS said.