Kianna Galvin, 17, disappeared on the afternoon of May 6, 2016, after telling her sister she was going to a nearby park in South Elgin.
Police said the handgun taken Monday from Forest View Educational Center has not been recovered.
Classes at Forest View Educational Center are set to resume Wednesday as police are confident gun is no longer on school grounds.
The 43-year-old is also accused of possession of drug paraphernalia and violation of bail bond, according to police.
A man was taken into custody Thursday after the 43-year-old resident was found dead in her home.
A family member of one of the victims interrupted the early morning incident before the suspect fled the scene, leaving a blood trail.
Officers were conducting a well-being check at the home Thursday night when they found the deceased woman.
The 28-year-old was pronounced dead at the scene of the incident near Hoffman Estates.
Attorney General Kwame Raoul said the Prospect Heights resident admitted submitting false Medicaid transportation claims.
The accused committed the crime against a person over the 60 years old or disabled, and was also charged with obstructing identification.
The nationwide effort, spearheaded by the U.S. Drug Enforcement Administration and local police departments, takes place twice a year.
The 44-year-old is also accused of driving on a suspended license, obstructing identification, and operating an uninsured motor vehicle.
Police said the student water gun game is not illegal, but look-alike firearms and trespassing could alarm residents.
An investigation continues into the incident that occurred Wednesday after police had attempted a traffic stop before the fatal crash.
Vehicle was later found submerged in a stormwater detention area near Industrial Avenue, police say.
The 26-year-old Arlington Heights man is accused of the incident in the in the 400 block of E. Palatine Road.
Alexis Ramirez, of Elk Grove Village, had gone missing last month after a single-car accident.
A group of five masked suspects involved in the incident were captured on security cameras at the home, according to police.
The 36-year-old Wonder Lake man faces five different charges stemming from the event.
Police said one of the three Rolling Meadows men arrested had a loaded handgun magazine protruding from his sweatshirt pocket.
Workers were cleaning the pond Friday afternoon when they made the discovery, police said.
Police said the morning incident occurred at a Huntington Bank location on Palatine Road.
Officials sent out a community notification regarding police activity Wednesday morning in the 1400 block of W. Palatine Road.
One of the accused is a resident of Denver, according to police.
Officials said the first-arriving fire crews were on scene within five minutes and found a fire coming from the second-story roof area.
The Wheeling man, who brandished a handgun equipped with a red laser and pointed it at the car occupants, was charged with five felonies.
A Mount Prospect resident had agreed to meet an online marketplace connection interested in the jewelry at the restaurant.
The arrests stem from an investigation into the January incident at the Republicans of Wheeling Township Building.
The 44-year-old Arlington Heights resident was arrested Thursday at Northwest Community Hospital.
The 41-year-old Arlington Heights resident was also charged with violating a bail bond, according to police.
Alexis Dumas faces multiple felony charges following the Friday night incident in Chicago's West Austin neighborhood.
An investigation into the Wednesday incident at a retention pond is ongoing.
Alexis Ramirez, 26, was last seen Tuesday near Higgins Road and Bond Street.
The 38-year-old Arlington Heights resident was arrested in the 1400 block of S. New Wilke Road.
The firefighter's family was making breakfast when a toaster oven ignited, resulting in a response from multiple area fire departments.
Victor Wembanyama posted an update on social media regarding his 23-year-old friend who never boarded his flight back to France last week.
Elijah Joseph Hoard, 23, who may require medical attention, was last seen at the airport on Friday, but never boarded his flight.
A 50-year-old woman, who police found dead outside a hotel earlier this week, was stabbed multiple times following a dispute.
The 19-year-old was also charged with having a blood alcohol concentration level of .08 or more and speeding, according to police.
Police said just after 7:30 a.m. on Feb. 19, they were called for a burglary in progress that turned out to be an armed home invasion.