Rescuers rushed to a frigid Minnesota lake Monday to save almost 200 fishermen who became stranded on a detached iceberg, according to authorities.

The urgent rescue began around 11:30 a.m. when anglers on Upper Red Lake called the Beltrami County Sheriff’s Office for help, Chief Deputy Jarrett Walton said in a press release. The callers told authorities that a large piece of ice broke off from the main shoreline and numerous people were stuck.

When first responders arrived, they saw about 30 yards of water between the broken-off sheet of ice and the shore, Walton said.

Drones helped pinpoint a narrow spot of separation where a temporary bridge was placed to evacuate the stranded fishermen, Walton said.

First responders also used the Integrated Public Alert and Warning System to notify other people on the ice who were unaware of the current conditions about where they could flee, Walton reported.  

But about 2:45 p.m., officials cleared about 200 people.

“The Beltrami County Sheriff’s Office reminds those who are thinking of heading on the ice that early season ice is very unpredictable,” Walton said in the release.

“Extreme caution should be used when heading on the ice and to check the thickness frequently to ensure an adequate amount of ice.”

Multiple agencies pitched in and airboats, water rescue boats and ATVs were deployed on top of the drones and temporary bridge used. 

Upper Red Lake is one of the first in the state to allow for ice fishing each year, said Shane Youngbauer, who owns a local business that outfits fishermen, according to the Star Tribune.

As a result, many will visit the lake from the end of November through early December, the newspaper reported.