The Latest on Illinois officer's death: Authorities expand search using 'saturation patrols'

Police officials follow Fox Lake Police Lt. Charles Joseph Gliniewicz's family after a vigil at Lakefront Park to honor him on Wednesday, Sept. 2, 2015, in Fox Lake, Ill. Gliniewicz was shot and killed Tuesday while pursuing a group of suspicious men. Police are searching for a second day to locate three suspects in the killing. (AP Photo/Nam Y. Huh) (The Associated Press)

Fox Lake Police Lt. Charles Joseph Gliniewicz's wife Mel, right, hugs a mourner during a vigil at Lakefront Park to honor him, Wednesday, Sept. 2, 2015, in Fox Lake, Ill. Gliniewicz was shot and killed Tuesday while pursuing a group of suspicious men. Authorities broadened the hunt Wednesday for the suspects wanted in the fatal shooting. (AP Photo/Nam Y. Huh) (The Associated Press)

A police explorer salutes as police officials follow Fox Lake Police Lt. Charles Joseph Gliniewicz's family after a vigil at Lakefront Park. (AP)

The latest on the fatal shooting of a police officer in northern Illinois (all times local):

8:30 a.m.

Authorities in northern Illinois have expanded their search for three suspects wanted in the shooting death of a police officer.

Lake County Sheriff's Office spokesman Sgt. Christopher Covelli says local and state police have been conducting "saturation patrols" in the Fox Lake area since late Tuesday night when they exhausted a search of a tighter, two-square-mile perimeter.

Covelli says that besides catching the offenders, the heavy police presence is meant to reassure the community. Seven schools were closed Wednesday out of concern for children's safety.

Authorities say 52-year-old Lt. Charles Joseph Gliniewicz was shot dead Tuesday morning while pursuing three suspicious men on foot in the community 60 miles north of Chicago.

The 30-year veteran was married with four children.