MINNEAPOLIS - Authorities pulled a second victim from the rubble Wednesday night, after a fatal building explosion and collapse at Minnehaha Academy.

At just before 10 p.m., Minneapolis Fire Chief John Fruetel announced that searchers had been able to locate and remove the body of the missing male victim, who had been identified by the school as 81-year-old custodian John Carlson, bringing the death toll to two. Carlson was pulled from the debris around 8 p.m.

Hours earlier, Ruth Berg, a longtime receptionist at the school, was found dead in the rubble.

Fruetel said the bodies were located in the same area.

Nine people were initially transported to Hennepin County Medical Center with injuries. HCMC tweeted at 6 a.m. Thursday that they are currently treating three people -- one is critical and two are in satisfactory condition.

HCMC has confirmed that the person in critical condition is Bryan Duffey. Minnehaha Academy's website lists Duffey as an assistant coach for the boys soccer team.

Six others have been discharged, they say.

Initially, three people were reported as missing, potentially in the rubble, but one person was found around noon, uninjured.

Because of hanging debris, Fruetel said they had to work methodically to find Carlson, while keeping their crews' safety a priority. They had been hoping to find him alive.

Chief Fruetel says investigators will work to determine the cause of the explosion in the coming days. The state fire marshal will likely take the lead, he says, but Minneapolis fire and other agencies may be involved.

The explosion happened after 10 a.m. at Minnehaha's Upper School on 3100 West River Parkway in Minneapolis. Officials suspect the explosion was caused when a contractor working on the building ruptured a gas line. Officers from the Minneapolis Police Department were called to the scene around 10:23 a.m.

A work permit issued by the city of Minneapolis to an Eagan-based company, Master Mechanical Inc., allowed for gas piping and a meter hook up. Master Mechanical sent out a statement, following the accident:

"Our thoughts and prayers are with everyone involved in this tragedy and especially with the families and loved ones of those who have died or who have been injured.

We are forever grateful to those first responders and bystanders who came to the aid of all of the injured, including our employees.

We continue to monitor the situation and are working in full cooperation with the Minneapolis Fire Department. At this time, we are referring all questions about the event to the Minneapolis Fire Department out of respect for their continued efforts.”

A work permit issued for Minnehaha Academy for "gas piping." 

Philip Day, who was with his daughter in the building, said a staff member ran up to them and told them they needed to evacuate immediately. "Seconds after that ... my daughter got up and was getting ready to leave out of the counselor's office and was blown back into the counselor's office by the explosion," he said. "I mean, it was seconds after they told us to get out that the explosion happened."

Day said before they knew it, they were surrounded by debris. "All the windows in the office blew out, rubble from the ceiling came tumbling down," he said. The counselor they were meeting with, Kristin Overton -- who is 7 months pregnant -- jumped over her desk and took cover, when the windows shattered and the ceiling came down. She said the explosion was instantaneous with their warning to evacuate. Day said the Minnehaha Academy community is very tight knit and will lean on each other in the days to come.

Those inside the gymnasium at the time say there was only a few seconds between someone saying they smelled gas and the building exploding. "As soon as they said, 'Hey, we smell gas, we gotta get out,' it exploded," said Tramon Vanlear, who was inside the gym. "I think the magnitude is the biggest thing I'm trying to comprehend right now."

A basketball team and a soccer team were practicing at Minnehaha at the time. Both teams managed to escape. Charlie Peterson was actually interviewing for a job at the school -- then ended up being one of three people rescued from the school's roof. "I got under the conference table and the ceiling came down and we got out the windows onto the roof and about 15 minutes later, they got ladders up to us," he said. Residents near the area say they could feel the explosion from their homes. Some say their power flickered briefly afterwards.

Minnehaha Academy before. 
Minnehaha Academy after. 

"It was just a really loud boom," said one resident. "You felt it in your chest." Dr. James Miner, chief of Emergency Medicine for HCMC, said during a news conference that this is something the hospital trains for and they were well prepared for the aftermath of Wednesday's explosion. He said there was also medical staff at the scene.

A prayer service was held at 7 p.m. at the school's lower and middle school, at 4200 West River Parkway. RELATED: Hundreds pack Minnehaha Academy prayer service

Gov. Mark Dayton issued a statement after being briefed on the incident. “My office is in continuous contact with the City of Minneapolis and the Minnesota Department of Public Safety, as emergency personnel respond to this emergency. The State will provide any and all resources necessary to aid first responders in their efforts to ensure the safety of all those impacted by this morning’s explosion. I thank the many firefighters, paramedics, and law enforcement officers who rushed to the scene this morning, and who are working still to ensure the safety of our children, adults, friends, and neighbors.”

Minnehaha Academy, a private school in Minneapolis, was built in 1912 and welcomed its first students in 1913. The South Campus was purchased and a chapel was erected in 1981. The Upper School currently serves grades 9-12, while the lower and middle school, 4200 West River Parkway, serves students from PreK to 8th grade. The school integrates faith and learning, through Bible study, chapel services and guidance from a Christian faculty and staff. "Today, the school remains dedicated to the Christian ministry set forth by its founders," according to the school's website. "This private, Christian school sponsored by by the Northwest Conference of the Evangelical Covenant church, serves approximately 900 students from the Twin Cities area."