10/10/2012 03:52 pm ET

Jacob Clarkson And Ross Livermore, Childhood Friends Attending University Of Wisconsin-Eau Claire, Die In Apartment Fire

Two University of Wisconsin-Eau Claire students who had been friends since the third grade were killed in an apartment fire on Monday morning.

The fire was discovered just before 6 a.m. on Monday. A fire was called in at 5:47 a.m. and crews were on the scene by 5:51 a.m. When fire fighters entered the apartment they found two unconscious bodies: Jacob Clarkson, 22, and Ross Livermore, 21, both computer science majors.

Clarkson suffered serious burns and died Tuesday at Hennepin County Medical Center in Minneapolis, according to the Pioneer Press. Livermore was killed in the fire.

Their roommates, Garret Isakson and Casey Malan, both 21, escaped the blaze and did not need serious medical treatment.

CBS Minnesota reports:

The Eau Claire Fire Department said the cause of the fire is still under investigation. The fire chief said they’re focusing on a back bedroom. They estimate the fire caused more than $100,000 in damage to the apartment building.

All four of them graduated from high school together in Stillwater, Minn, in 2009, where they were members of the pep band. They currently lived off-campus in an apartment above a real estate business in Eau Claire while going to UW. Livermore was also a trombone player in the school's marching band.

"These guys have been best friends -- all of them -- since the third grade," Brian Carlisle, dean of students at UW-Eau Claire, told the Pioneer Press. "They're very close to each other. One of their friends said to me: 'If you know one of them, you know all of them.'

Clarkson's family said in a statement to the AP their son would be an organ donor. They also thanked everyone "who kept our family in their prayers during this difficult time. Please continue to pray for us and also for Ross' family as we grieve the loss of our sons."

UW-Eau Claire is arranging for clothing, food and shelter for Isakson and Malan, Carlisle told the AP.