UPDATE: 8:30 a.m.

Police in Elmhurst and Villa Park had no immediate information about the early morning incident that brought out police from several jurisdictions, as well as a helicopter and police dogs.

Elmhurst police deferred comment to Villa Park police, who said no charges had been filed and no details were available related to the case.

UPDATE: 1:30 a.m.

Police say they have a burglary to a motor vehicle on Alma.

UPDATE: 1:20 a.m.

Suspect apprehended on the 300 block of Fairview. Elmhurst police say as soon as they determine he hasn't stolen or damaged anything in the 400 block of Alma, where he was earlier spotted by a resident, they will turn him over to Villa Park police.

UPDATE: 1:10 a.m.

Police chasing someone who matches the description of suspect on foot south of St. Charles Road near Fairview.

UPDATE: 12:30 a.m.

Helicopter still making passes over the area, but police are talking about breaking down the perimeter. They so far are unable to locate the suspect.

EARLIER:

Elmhurst police, with the assistance of Hillside, Villa Park, Oakbrook Terrace and DuPage County units, are searching for a 15-year-old who is wanted for aggravated assault out of Villa Park.

Police have set up a perimeter in an area around Sunnyside Avenue and Utley Road, between Elm Park Avenue and Alexander Boulevard. Police units also have been seen along St. Charles Road, west of York High School.

According to live reports over the police scanner, the suspect may be armed with a handgun. The suspect and another person not believed to be in the area are wanted for aggravated assault with a crowbar and a handgun. A helicopter unit out of Indiana has just arrived to assist, and K-9 units have been tracking in the area.

Patch will provide updates as they become available.