Chicago police officer and two other people were killed in an attack at a South Side hospital Monday afternoon that sent medical personnel and police scrambling through halls, stairwells and even the nursery in search of victims and the shooter before he was found dead.

Officer Samuel Jimenez, on the force less than two years, was gunned down as he went to the aid of other officers who had been called to Mercy Hospital & Medical Center around 3:20 p.m. about an assault. Jimenez, 28, was married with three small children. He’s the second Chicago police officer killed in the line of duty this year, the most since 2010 when five officers were fatally shot. The first was Near North District Cmdr. Paul Bauer, killed Feb. 13 outside the Thompson Center.

“Those officers that responded today saved a lot of lives,” said Chicago police Superintendent Eddie Johnson. “They were heroes because we just don’t know how much damage (the shooter) was prepared to do.”

Police had been called to the hospital after Juan Lopez, 32, confronted emergency room doctor Tamara O’Neal, apparently over a “broken engagement,” sources said. By the time Jimenez and his partner arrived on the scene, Lopez had shot O’Neal repeatedly, standing over her as he fired the last shots, according to police sources and witnesses.

“When they pulled up, they heard the gunshots, and they did what heroic officers always do — they ran toward that gunfire,” Johnson said. “So they weren’t assigned to that particular call, but they went because that’s what we do.”

Lopez, who sources say had a concealed carry license, exchanged gunfire with Jimenez and other officers as he ran into the hospital. Jimenez was shot in the lobby as Lopez continued firing. A squad car was hit, and a bullet hit the holster and lodged in the gun barrel of another officer, according to Johnson.

Dayna Less, 25, a first-year pharmacy resident, was hit as she walked out of an elevator. “That woman got off an elevator and was shot, why?” Johnson asked. Lopez was found inside the hospital, apparently suffering a wound to the head. Johnson said it was unclear how he was shot.

At a press conference late Monday night, Emergency Department director Patrick Connor grew emotional as he described O’Neal as dedicated to her church and patients. The 38-year-old physician graduated from the University of Illinois College of Medicine in Chicago in 2016 and had worked as a resident at Mercy for two years. She raised money for disadvantaged children and led her church choir, Connor said, choking up with emotion and pausing frequently.

“That was her one thing she wanted … to be able to go to church on Sunday,” Connor said, adding that they assured her she could. “We’ll make sure you go to church on Sunday.”

Less recently graduated from Purdue University and started working at the hospital in July.

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Michael Davenport, Mercy’s chief medical officer, said the hospital had conducted an active shooter drill last month. About 200 patients were being treated in the hospital on Monday, but authorities only evacuated the emergency room. The hospital’s emergency plans include barricading doors and ensuring patient safety.

In the confusion of the first moments, it was unclear how many people were shot, how many officers were among them and how many shooters there were.

As dispatchers and responding officers tried to make sense of the scene, reports came in of an officer shot somewhere in the lobby, a woman and an assistant also wounded. Finally, there was word of the gunman apparently shot in the head.

Even then, dispatchers continually checked on officers’ status and whether another gunman might still be on the loose.

“How many officers shot?” a dispatcher asked repeatedly.

“Trying to find that out,” an officer radioed.

Officers rushed to lock down the first floor of the hospital for a search, then closed off the stairwells. “We’re checking for victims,” a dispatcher said. “We also need officers on the third floor to check the nursery.”

By 4 p.m., the officer was being taken to the University of Chicago Medical Center, where he died.

Meanwhile, medical personnel continued to be brought out of the hospital by police, who radioed ahead to warn officers outside. At 4:40 p.m., the hospital tweeted that “patients are safe.”

Steven Mixon, an emergency room clerk, said he had received a call hours earlier, around 1 p.m., from a man he believed to be the ex-fiance of the woman shot outside the hospital. “He called and asked to speak with his fiancee,” said Mixon. “And she said, ‘Oh, just tell him I’m in with a patient.’ ”

Mixon said he got off work around 3 p.m. and waited for an Uber in front of the hospital. “I look up and I see her being harassed by some gentleman,” he said. “She was trying to avoid him and move around. And when she saw me, she waved for me to come that way.”

Mixon said he started to run toward his colleague to help when Lopez fired. “I guess it wasn’t my time to go because if I had made it to her, I would have been dead too,” Mixon said.

He watched as the gunman then shot at a police car and shot again at the woman, who had fallen to the ground. Mixon said he ran back into the emergency room, where it was “total chaos.”

“Everyone was running every which way,” he said. “We ran into surgery because they had locked doors. That’s when we heard more shots inside the hospital.”

Mixon said he remembers the woman looking beautiful this year at the hospital’s annual gala. “She was a sweetheart, just a sweetheart. What a fireball.

“Before all this, she was looking forward to getting married,” he said. “Talking about dresses, all of that. But then something happened and it was called off.”

James Gray was coming out of the clinic area when he said he saw a man in a black coat, black hat and dark pants shoot a woman three times in the chest. The man and the woman had been walking and talking to each other before the shooting, he said. The gunman stood over the woman and shot her three more times after she fell to the ground, said Gray. Then a squad car turned its lights on and came down the drive and the gunman shot at the squad car.

“It was chaos,” said Gray. “It was just mass chaos.”

https://www.chicagotribune.com/news/local/breaking/ct-met-shooting-mercy-hospital-chicago-20181119-story.html