The waters off Walton County, Florida, have been closed after back-to-back shark bite incidents in the county Friday.
Both incidents occurred in Walton County — which is in the Florida Panhandle — and not near a boat, but officials are unclear how far the attacks happened from the land, said McKenzie McClintock, the South Walton Fire District PIO.
The two incidents took place about 4 miles apart within about 90 minutes, South Walton Fire District Chief Ryan Crawford said. There were three victims in total.
It's "extremely unusual" for two bite incidents to occur in one afternoon, Crawford said during an evening news briefing.
The Hurricane season is on. Our meteorologists are ready. Sign up for the NBC 6 Weather newsletter to get the latest forecast in your inbox.
A 45-year-old woman was injured in the first "reported shark incident." It took place in the water around 1:20 p.m. in Watersound, in the area of Founders Way in Watersound Beach, Crawford and the Walton County Sheriff's Office said.
Crawford said the woman was swimming with her husband past the first sandbar when the bite occurred.
"She received significant trauma to the midsection, the pelvic area, as well as amputation of her left lower arm," Crawford said.
The woman was transported to a medical center in critical condition, Crawford said.
Following the first attack, the beaches in the surrounding areas flew double red flags to indicate the risk, the sheriff's office said. The Gulf in the Walton County area was also closed to the public at that time.
Soon after, at 2:56 p.m., the sheriff's office and fire department responded to a second shark incident at Sandy Shores Court area off Seacrest Beach in Walton County.
There were two victims in that attack, Crawford said: Two females between the ages of 15 and 17.
They were with a group of friends "just inside the first sandbar," Crawford said, which makes the location "very similar" to the first attack.
The first victim had "significant injuries" to one upper and one lower extremity, Crawford said. She was transported to a trauma center in critical condition.
The second victim had "flesh wounds" to her right foot and is in stable condition, Crawford said.
Walton County Sheriff Mike Atkinson said both women in critical condition have a "fighting chance," thanks to quick responses from nearby citizens as well as first responders.
After the second attack, officials closed the water to the public in all of Walton County.
McClintock said officials do not know what kind of shark bit both victims, but there are often sharks in this water.
Officials on Friday said they needed some time before they let people return to the water and added that they will likely reassess the situation Saturday.
Officials have reached out to experts at Mote Marine, out of Sarasota, Florida, Atkinson said, to see if there is anything "anomalous" about the dual attacks, although he said he doesn't think there is.
This story first appeared on NBCNews.com. More from NBC News: