ST. PAUL, Minn. — Parents whose children went on a field trip that left two students dead and injured two others say they should have been warned that parts of the St. Paul park were hazardous.

While the city warns people who lead groups about the dangers of Lilydale Regional Park, officials at Peter Hobart Elementary School in St. Louis Park did not relay that warning to parents of the fourth-graders who made a fossil-hunting trip there in May, Minnesota Public Radio and KARE-TV reported.

"They should have consulted with us and let us know: The area's not a very safe area. There's caves. There's cliffs. Are you OK with us taking your child down there?" said Danielle Meldahl, whose 10-year-old son, Devin, suffered leg, skull and rib fractures in the landslide. "I don't think I would have let Devin go if I knew the situation."

Lilydale Regional Park runs along the Mississippi River. It's a popular destination for fossil hunting, which requires a permit from the city.

The application form makes park users acknowledge that "some of the conditions and locations within the Lilydale Regional Park area are hazardous to persons or property." It also requires the applicant to assume liability for any injuries that happen due to the park's "unsafe conditions."

A teacher applied for the permit online and clicked a box agreeing to the city's waiver, according to documents released by the city. The waiver also requires applicants to "accept responsibility for making these conditions known" to everyone in their tour group, including the parents of minor children.

But the field trip information sheet the school sent home to parents didn't mention the potential danger, only saying students should "be prepared for hiking, climbing, and getting muddy," MPR and KARE said in jointly investigated reports Wednesday (http://bit.ly/18EW5jc and http://kare11.tv/145uxBV).

St. Louis Park Public Schools declined to make staff or administrators available but released a statement.

"Despite our sadness over this incident, the School District is attempting to move forward as best as it can," the statement read in part. "We currently are preparing for the 2013-14 school year. While our plans are directed toward the future, the School District will continue to provide additional support for the students, families and staff impacted by this tragedy, as they have not been forgotten."

The Meldahls are exploring their legal options, as are the parents of Mohammed Fofana and Haysem Sani, the two students who died.

Winning a lawsuit could be difficult because Minnesota law makes it harder to sue a governmental institution than a private one, said attorney Bob King, who once won a settlement from Roseville schools after a student drowned on a field trip but isn't representing these families.

"If there is a lawsuit, it's going to turn on what a reasonably prudent school district would've, should've done," King said.

The district said it "continues to gather information as to what occurred" but declined to discuss what it has learned, saying that information is confidential. State law allows public institutions to keep information secret if it's collected in anticipation of a lawsuit.

The fossil pit remains closed as the city investigates. Geologists say rain likely played a role in the landslide, as there was light rain the day of the field trip and several inches had fallen the week before.

Four days after the slide happened, Sani's father, Mohamed Muse, hiked in and shot cellphone video.

"This is a dangerous place," he said on the video as he surveyed the cliff rising above the pit and the pile of rocks at its base. "How they going to bring the kids here?"