PHILADELPHIA >> The impact area where a medical transportation plane crashed in Philadelphia was notably “expansive,” U.S. Transportation Secretary Sean Duffy said Monday after viewing the site with investigators and city officials.

Duffy said he was struck by “how expansive it was. And the issues that fire and police were dealing with. Again, this is a very populated area.”

The crash Friday evening killed all six people on the Learjet 55 air ambulance, including a girl who had been receiving medical treatment at Shriners Children’s Philadelphia hospital.

A seventh person inside a vehicle was killed on the ground.

Mayor Cherelle Parker said two more people who were hurt on the ground have been identified, bringing the total to 24. Four people remained hospitalized Monday, two in critical condition.

Parker said footage of the crash has made her “think about what could have been, had a gas line been hit.”

Jet Rescue Air Ambulance said the plane had been taking Valentina Guzmán Murillo, 11, and her mother, Lizeth Murillo Osuna, 31, home to Mexico. It plummeted within a minute of taking off from Northeast Philadelphia Airport.

Jet Rescue identified its team members as Dr. Raul Meza Arredondo, 41; the captain, Alan Montoya Perales, 46; the copilot, Josue de Jesus Juarez Juarez, 43; and paramedic Rodrigo Lopez Padilla, 41.

Valentina had recently completed treatment for a condition not easily treated in Mexico, hospital officials have said.

Debris from the crash exploded into a fireball, and pieces of the plane were blown into the residential and commercial Castor Gardens neighborhood, severely damaging several businesses. City officials said four homes were destroyed, six sustained major damage and 11 were otherwise damaged.