Torrential rains unleashed flash floods along the Guadalupe River in Texas on Friday, killing at least 24 people as rescue teams scrambled to save dozens of victims trapped by high water or reported missing in the disaster, local officials said.

Among the missing were 23 to 25 people listed as unaccounted for at an all-girls Christian summer camp located on the banks of the rain-engorged Guadalupe, authorities said.

At a news conference late Friday, almost 18 hours after the crisis began, Texas Gov. Greg Abbott said search-and-rescue operations would press on through the night and into Saturday.