LIBERTYVILLE, Ill. (STMW) –– A forest preserve in north suburban Libertyville reopened Saturday morning after officials determined a bomb threat risk had passed, and declared the area safe for public use.

All regularly scheduled events and activities have resumed at the Independence Grove Forest Preserve, according to a release issued by the Lake County Forest Preserve District Saturday morning.

The district received a bomb threat through a letter in the mail earlier this week, which targeted a private event and not a district function. Federal authorities were notified immediately after the letter was discovered.

The preserve was first closed Tuesday night, July 16, just before a concert. Attendees were ordered to leave and refunded their $5 parking fee.

“Extensive search efforts” throughout the week uncovered no suspicious devices or materials anywhere on forest preserve property, the release said.

“The bomb detection canine teams made multiple sweeps of the preserve, which helped us to expedite a thorough search effort and to reopen the preserve sooner than would otherwise have been possible,” said John Tannahill, chief of the Lake County Forest Preserve Ranger Police.

“First and foremost on our minds was to secure the site and protect the public so no harm would come to them from this threat,” said Ann Maine, president of the Lake County Forest Preserves Board. “We are grateful for the sympathetic support and understanding we have received from our preserve visitors during the closure of Independence Grove.”

Because the threat was sent by mail, the U.S. Postal Investigation Service will lead the ongoing investigation. The USPIS has gathered and sent evidence to their lab for processing and interviewed persons of interest in relation to the threat, but no arrests have been made.

Authorities are questioning three suspects, officials said previously.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2013. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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