CHICAGO (CBS) — As the emergency room at Mercy Hospital reopened Tuesday after gunman Juan Lopez’s rampage, those who work there have heavy hearts after losing two colleagues.

“For today, obviously, it’s like a SWAT team of grief counselors, that are going to be here all day, hitting every unit and every individual,” said Michael Davenport, the hospital’s chief medical officer.

“They’ll be available as long as our people need. There’s nothing more important than healing the healers.”

Davenport thanked the Chicago Police Department for their bravery and courage in protecting the hospital yesterday adding each of them are mourning the death of Officer Samuel Jimenez.

Lopez, 32, shot and killed his former fiancée, Dr. Tamara O’Neal, in the parking lot outside Mercy Hospital and Medical Center, after the two were seen arguing outside.

He fired at police officers responding to the shooting, damaging a squad car, before entering the hospital.

He shot and killed 24-year-old Dayna Less, a pharmacy resident at Mercy, as she exited an elevator.

He shot and killed Chicago Police Officer Samuel Jimenez, one of the officers who confronted him inside the hospital.

He was shot and killed inside the hospital. Police have said it’s unclear if he shot himself, or if he was shot by the SWAT team.