4 Illinois hostages rescued

• 4 remaining hostages rescued Wednesday morning, nearly a day after situation began


• Police: 2 officers responding to Tuesday's robbery were shot in Harvey, Illinois


• The suspects took people hostage inside a home, police add


• Law enforcement from around Illinois converged on the residence

(CNN) -- Law enforcement officers forcefully but safely ended a two-day hostage situation at a suburban Chicago house Wednesday morning, rescuing two children and two women while taking two suspects into custody in a raid on the home, authorities said.

The move -- made after four other hostages were released the previous night -- finished a roughly 20-hour standoff that police say began with a robbery attempt at the home in Harvey, Illinois.

The hostage-takers shot and injured at least one police officer when the standoff began Tuesday, but no shots were fired and no one was hurt when police moved into the home Wednesday, having determined negotiations were no longer progressing and that tensions were rising.

Police: Robbery suspects holding hostages

"We're very happy that there's been a peaceful resolution," Cook County Sheriff Tom Dart told reporters.

The four rescued hostages, including a 6-year-old child and a 12-year-old girl, were "traumatized" but unharmed, Dart said.

Police knocked down a first-floor door and rushed up to the second floor, where they found the hostages and the suspects. Authorities decided to move after round-the-clock negotiations "were getting a little bit more on the dicier side," Dart said.

"It was the (proper) time to act," Dart said.

Started with robbery attempt

The incident began at about 12:45 p.m. Tuesday when two people tried to rob the home, Dart said.

Inside the home when the suspects arrived were four children from one immediate family, plus two children who are related to them, and the two women, Dart said.

Police were called, and one responding officer was shot in the arm but is OK, Dart said. Another officer was injured and also is OK, Dart said, without elaborating.

Sometime afterward, law officers from all over Illinois surrounded the residence and began the negotiating process.

Four hostages -- children ranging in age from 1 to 12 -- were released Tuesday night and were not injured, police said.

Dart said the talks persisted for hours and proved to be a "very thoughtful approach" to hostage negotiations. Then, the back-and-forth stalemated and "the time had come for certain action," Dart said.

"At this juncture it was the prudent thing to do, which was to enter the house and to secure the hostages to make sure they weren't being harmed," Dart said.

Asked if police and the suspects were in a struggle, Dart answered: "They didn't surrender themselves."

There's no indication that the suspects had any connection to the hostages before Tuesday, Dart said.

Harvey Mayor Eric Kellogg had asked residents to stay inside their own homes as police, who blocked off nearby streets, dealt with the situation.

A city of about 25,000 people, Harvey is about 20 miles south of Chicago.

CNN's Bill Kirkos and Greg Botelho contributed to this report.