Christmas came early for Melissa Siedenstricker, a 29-year-old property manager of a luxury apartment building in downtown St. Paul.

On Thanksgiving Day, her brother Jake gifted her a cold-weather suit. He knew she was yearning for an early ice fishing trip, and she made a break for Upper Red Lake last Friday with Zeth Knyphausen of Stacy.

Melissa was a partier, Jake said, and she delighted in meeting up that night with fellow members of the Hard Water Zombies at the bar at Rogers on Red. Her blithe Snapchat greetings from the campground and RV park suggested that Upper Red was rocking with the earliest of early-season ice anglers.

Forty-eight hours later, when the weekend’s gold rush for walleyes was mostly over, Melissa and Zeth were reported missing by the Beltrami County Sheriff’s Department. A desperate search on Monday ended when Jake found his sister’s boot on thin, slippery ice bordering a large swath of open water. Melissa and Zeth had gone under, along with Zeth’s four-wheeler, in 12 feet of water. They were about a mile from shore and no one knows exactly when or how it happened.

As families of the two drowning victims grieve and public safety officials amplify safety warnings to ice anglers, investigators continue to look for answers. So far, the incident has the makings of a quintessential Minnesota tragedy.

“People are pushing the envelope so much,’’ Beltrami County Sheriff Phil Hodapp said Wednesday. “It’s like people aren’t accepting reality anymore.’’

Hodapp estimated that 1,800 people flocked to Upper Red Lake last weekend despite sketchy ice conditions that included miles-long cracks of open water and unpredictable shifting and thinning of ice. The lure — unique to Upper Red — is the combination of an increasingly abundant walleye population in water that freezes early because of the lake’s shallowness and northern latitude. Moreover, the best winter walleye bite on Upper Red happens early.

“People come from a long way away for our early ice,’’ said Greg Vollhaber, chief of the Kelliher Fire & Rescue crew. “But things can get bad in a hurry.’’

Hodapp, Vollhaber and DNR Conservation Officer Kyle Quittschreiber all said that Upper Red’s resort owners provide safety-conscious maps to users of their privately maintained ice roads. The businesses also mark the ice with cones and other objects. But conditions can change rapidly, and Quittschreiber said it can be difficult at night for some anglers to make sense of all the markings.

Already this year, the game warden said, more than 10 people have fallen through the ice on Upper Red. Some have saved themselves, while others have been rescued. At night, there’s an increase in the number of anglers who call 911 to say they are lost on the ice.

“I think we see more people coming up here who are not prepared for the weather or the conditions,’’ Vollhaber said.

The local fire and rescue chief has 30 years of experience. Over his first 20 years, he remembers only one rescue of an ice angler. But since 2006, after tribal and DNR fisheries managers revived walleye stocks, the lake has accommodated more and more fishing pressure. This year’s winter possession limit of four walleyes per angler is the largest ice fishing bag allowed on Upper Red in more than 17 years.

Vollhaber said the fishing boon has coincided with a dangerous push of safety limits. If the fish aren’t biting where resort owners say it’s safe to drop a line, some visitors stretch the boundaries and attract followers when they post their catches on social media.

“Until seven years ago, we didn’t have any real [rescue] equipment to speak of,’’ Vollhaber said.

Growing up

Jake Seidenstricker said he and his sister grew up in the Mille Lacs area, fishing a lot as kids. They spent a lot of time in their youth at a family cabin on Leech Lake and in recent years Melissa was getting back into hunting and fishing. Besides managing Penfield, a five-star apartment building, she was a student at the University of Minnesota with dreams of going to law school.

Jake said Melissa and Zeth were “just friends” who ice-fished together last year on Red Lake and Lake of the Woods. They were both experienced in the outdoors and Zeth hunted or fished on most weekends. Zeth’s father, Terry Knyphausen of Stacy, said his son also enjoyed auto racing, visiting Alabama’s Talladega Superspeedway in mid-October.

Terry’s first inkling of trouble on Upper Red came early Monday morning when Zeth didn’t show up for work in the maintenance department at a tool manufacturing plant near Hugo. Terry gathered other family members for a hasty drive to Rogers on Red, 60 miles north of Bemidji.

There, resort owner Chris Freudenberg was telling everyone that Melissa and Zeth had returned to the resort “around brunch time’’ on Saturday. Freudenberg said he talked with the couple before they headed back to the ice. They were on a camo-painted Polaris 500, and it was the last time anyone reported seeing them.

Jake Seidenstricker said he doubts Freudenberg’s account and believes Melissa and Zeth were last seen Friday night at the resort’s bar. The two were to meet up again on Saturday with their friends from the Hard Water Zombies, but the meeting never happened.

Seidenstricker said he thinks the drowning happened after the couple left the bar at night. That’s because a random fisherman told him he spotted a portable fish house floating in the water early Saturday morning where Melissa and Zeth were later found. The couple had been carrying the collapsible fish house on a trailer towed behind Zeth’s four-wheeler.

But in an interview, Freudenberg insisted he discussed fishing with Zeth and Melissa on Saturday, roughly around 10:30 or 11 a.m. He said he didn’t want to “jab back’’ at angry family members who have accused him of fabricating the story to cover up for an alleged nighttime accident that might be related to drinking.

“The family right now is mad and angry,’’ Freudenberg said. “There’s nobody hiding anything or covering up.’’

Terry Knyphausen said his own anger stems from Red Lake resorts promoting early-season ice fishing when the lake isn’t safe. Melissa and Zeth fell into a known trouble spot — open water the size of a football field — that was northwest of the “sleeper’’ fish house they rented from Freudenberg.

The resort had marked the hazard with a single cone even though Freudenberg said it was beyond his resort’s boundary. He also said the spot was marked on the resort’s map with a skull and crossbones.

Terry Knyphausen said the maps are a farce and the markings on the ice are scant, even in daylight.

“This ice is so unsafe and they are promoting how safe the ice is: ‘Come on up,’ ’’ he said. Autopsy results could shed light on when the drownings occurred. Jake Seidenstricker said there were signs at the scene that the two struggled to get out of the water, breaking their fingernails and injuring their fingers.

During the week, Beltrami County issued a rare news release warning people to stay off Upper Red Lake this weekend. “Anyone attempting to go onto the ice does so at their own risk,’’ the notice said.